Bile had nothing to do with the creation of the primarches - he was too young, and also was on Chemos. his attempt was to unlock the secrets that led to the primarches. he is also one slippery character, so it was probable that abbadon didn't have the chance to get hold of him.
also abbadon was initially grief stricken at horus' death, it wasn't until he had had time to dwell that he got angry, and that in truth is probably because Horus showed remorse in his final moments and so went against the 'creed' he had taught his legion to follow.
as for Biologically descended, thats what GW hints at, but im not so sure. The Primarches seem to have been heavily influenced by their enviroment in their early years, so who isn't to say that rather than looking like him, he doesn't look like them? |