Detect thoughts or Zone of Truth would have done the trick.
Both have saving throws, and with the latter, you don't even know if an individual made the save or not (I guess you don't technically know with
detect thoughts, either, but if you don't actually detect any thoughts, it's probably safe to assume they made the save).
Zone of truth is occasionally good at getting the truth from someone, but it's of little use in telling whether someone is lying or telling the truth. They'd want
discern lies, but that's higher level, and still gives a save -- but since it's targeted, at least you'll know if they make it.
Also, I thought it was funny.
Also #2, I'm pretty sure the two Azurites pictured are not paladins; neither are wearing the blue cloaks, for one thing. One's not even wearing armor -- pretty sure that's
a spellcaster of some sort some other type (I looked, and he is using a katana -- maybe some sort of eldritch knight?). The other's probably just a warrior. Remember, most of the paladins (all of the experienced ones) in Azure City were in the throne room to protect the gate, and were mostly slaughtered by Xykon and/or blown up by the gate. Some, like Thanh (the mustached paladin leading the resistance), were away from town when the battle went down. Aside from them and the ones that got out with Hinjo, I'm pretty sure there aren't many paladins left.