[ Lambert has already guessed that much... ]

The short answer is maybe. [ And he knows that's unsatisfactory, so he'll continue. ]

Thinking the servants can't help themselves assumes the servants aren't fae themselves, which we don't know for a fact. My guess is that it's probably something like what the Ringmaster's got here. Some people signed up willingly, some people got tricked into it, they're tied to the Prince with magic one way or another.

Which means I don't trust them.