True.
In Context it allows God the Father to be in that meeting.
In context it allows for the Holy Spirit to be "The third person of the Godhead" -- no SDA doctrine treats this as meaning that there was not a Triune Godhead at that time.
Before the entrance of evil there was peace and joy throughout the universe. All was in perfect harmony with the Creator's will. Love for God was supreme, love for one another impartial. Christ the Word, the Only Begotten of God, was one with the eternal Father,—one in nature, in character, and in purpose,—the only being in all the universe that could enter into all the counsels and purposes of God. By Christ the Father wrought in the creation of all heavenly beings. "By Him were all things created, that are in heaven, . . . whether they be thrones, or dominions, or principalities, or powers" (Colossians 1:16); and to Christ, equally with the Father, all heaven gave allegiance.
No Bob, in context it says He is the only being who could enter into all the counsels and purposes of God.
And note the statement in the same chapter:
"Sin originated with him who, next to Christ, had been most honored of God and who stood highest in power and glory among the inhabitants of heaven."
She is indicating Christ as honored of God among the inhabitants of Heaven. And He is the one who can enter into the councils of God.
And another quote, this time from the Spirit of Prophecy, on the same theme, from the parallel chapter on satan's fall:
Christ had been taken into the special counsel of God in regard to his plans, while Satan was unacquainted with them. He did not understand, neither was he permitted to know, the purposes of God. But Christ was acknowledged sovereign of Heaven,
his power and authority to be the same as that of God himself.
There was contention among the angels. Satan and his sympathizers were striving to reform the government of God. They were discontented and unhappy because they could not look into his unsearchable wisdom and ascertain his purposes
in exalting his Son Jesus, and endowing him with such unlimited power and command. They rebelled against the authority of the Son. 1SP 18.2
Angels that were loyal and true sought to reconcile this mighty, rebellious angel to the will of his Creator. They justified the act of God in conferring honor upon Jesus Christ, and with forcible reasoning sought to convince Satan that no less honor was his now than before the Father had proclaimed the honor which he had conferred upon his Son. They clearly set forth that Jesus was the Son of God, existing with him before the angels were created; and that he had ever stood at the right hand of God, and his mild, loving authority had not heretofore been questioned; and that he had given no commands but what it was joy for the heavenly host to execute. They urged that Christ's receiving special honor from the Father, in the presence of the angels, did not detract from the honor that he had heretofore received.
The loyal angels hasten speedily to the Son of God, and acquaint him with what is taking place among the angels. They find the Father in conference with his beloved Son, to determine the means by which, for the best good of the loyal angels, the assumed authority of Satan could be forever put down. The great God could at once have hurled this arch deceiver from Heaven; but this was not his purpose. He would give the rebellious an equal chance to measure strength and might with his own Son and his loyal angels.
All the heavenly host were summoned to appear before the Father, to have each case determined. Satan unblushingly made known his dissatisfaction that Christ should be preferred before him. He stood up proudly and urged that he should be equal with God, and should be taken into conference with the Father and understand his purposes. God informed Satan that to his Son alone he would reveal his secret purposes, and he required all the family in Heaven, even Satan, to yield him implicit, unquestioned obedience; but that he (Satan) had proved himself unworthy a place in Heaven.
Now in the later chapter regarding the fall:
Sorrow filled Heaven, as it was realized that man was lost, and the world that God created was to be filled with mortals doomed to misery, sickness, and death, and there was no way of escape for the offender. The whole family of Adam must die. I saw the lovely Jesus, and beheld an expression of sympathy and sorrow upon his countenance. Soon I saw him approach the exceeding bright light which enshrouded the Father. Said my accompanying angel, He is in close converse with his Father. The anxiety of the angels seemed to be intense while Jesus was communing with his Father. Three times he was shut in by the glorious light about the Father, and the third time he came from the Father his person could be seen. His countenance was calm, free from all perplexity and trouble, and shone with benevolence and loveliness, such as words cannot express. He then made known to the angelic host that a way of escape had been made for lost man. He told them that he had been pleading with his Father, and had offered to give his life a ransom, and take the sentence of death upon himself, that through him man might find pardon; that through the merits of his blood, and obedience to the law of God, they could have the favor of God, and be brought into the beautiful garden, and eat of the fruit of the tree of life. 1SP 45.1
And as they should witness his sufferings, and the hate of men towards him, they would be stirred with the deepest emotions, and through their love for him, would wish to rescue and deliver him from his murderers; but that they must not interfere to prevent anything they should behold; and that they should act a part in his resurrection; that the plan of salvation was devised, and his Father had accepted the plan.
Jesus bade the heavenly host be reconciled to the plan that his Father accepted, and rejoice that fallen man could be exalted again through his death, to obtain favor with God and enjoy Heaven
Said the angel, Think ye that the Father yielded up his dearly beloved Son without a struggle? No, no. It was even a struggle with the God of Heaven, whether to let guilty man perish, or to give his beloved Son to die for them.
Now Bob, if you can read through those quotes and see a "Trinitarian" concept, your Trinity detector is malfunctioning.
Christ had been "taken into" the special counsel of God? Christ's power and authority were the same as that of "God Himself? The angels have to acquaint the pre-incarnate Son of God with what is going on? Jesus has to be endowed with unlimited power? "The Great God" could at once have hurled the deceiver from Heaven but gave the rebellious an equal chance to measure strength and might with "His own Son?" satan demands that he be taken into conference with the FATHER and understand His purposes.
And after the fall Jesus goes to the Father, not the Holy Spirit and the Father, and offers His life. Now later she wrote that it was decided before the fall. But in this account the Son is pleading with the Father (not the Spirit and the Father), after the fall.
Bob, this is not describing the Trinity.
In context it reminds us that Lucifer wondered why he was not included - but does not say anything about "Lucifer thought the Holy Spirit should not be included - but could not figure out why Lucifer would not be included" - so then there was never a time when SDAs thought this meant that the Holy Spirit - the third person of the Godhead - was being excluded from something.
Of course there was Bob. Because the majority of Adventists at this time thought the Spirit was a force without a personality, as the history articles point out. And Ellen White did not mention the Spirit having a personality or being part of the Godhead until the 1890's. Moreover, there is no Holy Spirit mentioned at all, and satan wants to be taken into conference with the Father--because he was jealous that the Son was.