I dont know about that. I think that the 5D humans descended from the original humans, not the embryos.
I wonder if in the original timeline, the Earth (and its population) dies. Then Anne Hathaway "raises" the embryos. The descendants of the embryos become advanced enough to create the Tesseract. And finally create the wormhole allowing us to alter our timeline so that both lines of humanity survive.
By the time the 5D humans came to exist, it wouldnt matter who were their ancestors anymore. But trying and actually altering that could be catastrophic, and really it woudnt change a thing. I mean, the Tessaract was build specifically for Cooper, so that he could find Murph and send her the message. The 5D humans already knew that it would be like this, so that means it should have already happened, because they can percieve time as a physical dimension, and such are aware of how everything came to be.
As such, The Tessaract was build by the 5D humans to gurantee their existance, which means that they had to have been originated from the original humans. Theres no point in ensuring plan A if they came from plan B.
Its funny how some people call this incredibly original and creative ending "stupid". It was easily the second best part of the movie for me, the first being Dr Mann subplot.