Happy new year,
But your whole question is based on the wrong assumption that there will be marriage at that time.
What’s your source for this?
Based on the teshuvos that I quoted, there will be marriage during תחיית המתים, and I have never seen otherwise.
Re your proof from the Gemara (Avoda Zora 5a) about the עגל: The Gemara concludes there that they would have children, but since they would live forever, the children would have no importance, because they would always be compared to the greatness of their parents’ generation.