If your microbots will be confirmed as the main in-universe force and explanation behind enforcing strict racial requirements, that will be pretty stupid IMO. I can't see any reason for them to be configured that way, since their main declared function revolves around Steele's survival through adaptation.
But simulteneously it would allow for a pretty easy solution through @Couch's Steele Tech Biomedical Division and Dr. Lessau, as soon as powers that be approve of the new system.
There's no other way I can think of to explain why changing your ears and only your ears, makes your nuts change too.