iserith
Magic Wordsmith
The player always determines what the character thinks, does, and says. They are not compelled to act in any particular way when they are unable to tell if the NPC is lying. A failed Wisdom (Insight) check does not indicate the character believes anything in particular, only that they were not able to detect any untruthfulness in the NPC given observation.No, they cant.
I mean they could, but that shithouse roleplaying, in addition to being metagaming, and has no place at my table.
If your PC fails his Insight vs a Deception, the PC believes the lie to be true, and the Player should play the character accordingly.
If my NPC fails my Insight vs your PCs Deception, I'll do the exact same thing.
In addition, there is no prerequisite to guarding the door or disabling it. Those things can happen whether Han believes the voice or not (as established by the character) or even if that entire exchange over the intercom never happened. But imagine after failing the check, Han's player says, "Ha! Pulled one over on that guy. Chewie, guard the door in case someone else happens to wander in here and spoil our plans." No good?