Examination room (spoiler)

[Thaliur]

You need to add the glowing crystal, as far as I remember. You'll find it in a kind of quarantine chamber.

That might be compound 65 that you get by playing the crane game?

Yes, from the crane/claw machine. Sorry, I thought compound 65 was something else, I haven't played Black Plague in a long time.
Did you add all six bottled chemicals?