The repeater trustee could be in violation if s/he knows what's going on and does nothing to stop it.
Of course, in a genuine life-or-death emergency, if there is no alternative, anybody can use any radio facilities available to summon help. But that's not the case here.
The bigger question is:
Why do you ask?
73 de Jim, N2EY
I have noticed the latter on the local repeater, on several occasions, (146.64) and there are others that think differently. (Sometimes in a real heated demeanor). Others are thinking differently in a sense that the trustee of the repeater is solely responsible and not the licensed Amateur that is having the conversation. I would suspect that if the FCC did warrent action that BOTH (the licensed Amateur and the repeater trustee) along with the unlicensed operator would be in violation of several Part 97 sections.
Appreciated your opinion and candor!