Learned this one dealing with bureaucracy at uni - and don’t leave someone’s office until you know where you’re going next. “I can’t do that” - no problem, who can, and where can I find them?

Incapable of saying yes or not authorized to approve?

I don't think "incapable of saying yes" is a thing.

Some people are so terrified of saying yes, having it go wrong, and getting blamed for the consequences that they come across as pathologically incapable of saying yes. I have worked for such people. Briefly.