But the issue isn't lynching him or not lynching him
It's your unwillingness to- completely in private and with minimal risk - extract more information out of his claim. It comes across as digging your heel into this position more than the exact set of circumstances justify, even if you're staking that as your position.
If I presume you are town, that you have a parasitic indie, an indie who you've declared is possibly beneficial and you have a good repoire with, and despite claiming you offered nothing you could do to gather information.