It really should go without saying that this would be a pretty major retcon. Mindflayers used to be heavily restricted over which creatures could be turned into a mindflayer due to, y'know *biological compatibility*. Obviously a tadpole can't consume and replace/merge with the host brain if it has none to begin with, and mutating a metal and wood frame into a fleshy mindflayer body? Yeah, I challenge anyone to see that play out in a cutscene and not immediately get pulled right our of their immersion.
