Here's some context to Ezekiel 28 - I know that a lot of people insist that the subject of the chapter, the prince of Tyre is actually Satan. No, sorry, for these reasons:
The previous two chapters had been all about the literal city of Tyre and the bad fate God had in store for it. Chapter 28 is about the prince of the same literal city, and there is no subject break until toward the end of that chapter.
God says, “…thou art a man and not God…” (verse 2) - but if this prince was really Satan, don’t you think God would have said so? No – it’s a literal city, a literal prince, and a man at that.
Verse 8: “They shall bring thee down to the pit, and thou shalt die…”. The previous verse speaks of terrible strangers who draw the sword against this prince, but Satan cannot be taken down with literal swords, as he is a spirit being.
Verse 13: “Thou hast been in Eden…”. This does not mean that the prince of Tyre was in the garden of Eden with Adam and Eve – as ever, it’s all in the context. See 27:23: “Haran, and Canneh, and Eden, the merchants of Sheba, Asshur, and Chilmad were thy merchants.” Eden is treated as a literal country like any other literal country of the time. For more on this subject, see the books of David Rohl especially Legend. However, do not think that I agree with all of Rohl’s conclusions.
In view of all the above I must confess that I find 28:14, which is the crux of the whole Satan argument, to be a puzzle, but I’m not going to set one verse against the context of three chapters of text.
As for Death and the defeat of it, I see that you are SDA, so I don't see any further profit in trying to convince you, for Sister White has spoken...well sort of. I noticed in her writings that she put forth an annihilationist position, but at other times she spoke of people going to Hell. Neither involves the complete defeat of Death.