Simpsons did it?
I think this scene calls for an insight check which I'll give a go once I'm off work and have access to my dice rollers. I believe Vlad put proficiency in insight too or if there is some spell or another, he may have ideas on how to glean the sincerity from our captive.
Actually, we pretty much have the Powerpuff Girls as far as I can tell.
Akilah is Blossom
Najiyah is Bubbles
Ankabut is Buttercup
Here to save the City of Sheikhville.