thank you so much for such a detailed review!! all valid feedback, i really appreciate it!
re: alien ending, that's strange!
my theory is (hint below):
after knifing the eye out, did you also sew it up? i totally did not make that clear so it's my bad design, but only after going through that step as well will the eye actually alter on the full human. this + 2 slimy things which you correctly identified would achieve the ending.
thank you again for playing!!