Whilst I wouldn't want that scene reinserted in Alien, for the same reason
Scott cut it in the first place, I don't see why it isn't plausible anyway.
Cameron kinda reduced the alien to terms that we could understand and be
familiar with (insects). The idea of turning victims into hosts is perhaps too
out-of-this-world for the popcorn-munchers who so adore Aliens.
It's a pity the whole idea was cut from Alien 3, in fact. That might have gone
some way to providing that original spin the film so very much needed.