KluteDavid said "The wild olive branch represents the Gentiles as a whole, "
Paul is describing individuals in Romans when referring to gentiles as wild branches.
I and You are singular persons, not all gentiles.
It sounds to me like your teaching only the nation Israel was elect.
17 And if some of the branches were broken off, and you, being a wild olive tree, were grafted in among them, and with them became a partaker of the root and fatness of the olive tree,
18 do not boast against the branches. But if you do boast, remember that you do not support the root, but the root supports you.
19 You will say then, “Branches were broken off that I might be grafted in.”
20 Well said.Because of unbelief they were broken off, and you stand by faith. Do not be haughty, but fear.
21 For if God did not spare the natural branches, He may not spare you either.
Does God treat all gentiles as one being? No. Do all gentiles get grafted into the true vine, No.
See for you to teach this means you're teaching a universal salvation, that all gentiles are grafted as a group onto the True Vine.
And your teaching if one falls they all fall, if one is saved, all are saved.