I would:
1) kill the informant right then and there and say he went insane and tried to attack the lord (from which you just prevented). They were going to kill him anyway eventually.
2)Ignore the previous offer from the lord, ask for payment that was due, and a bonus for saving the Lords life.
3)If the Lord doesn't seem to get the message of who holds the power here, I would then back it up by displaying a bit of power somehow ( a room full of golem scorpions/spiders?).
This way he keeps his loli, gets paid, and protects his innocence (if the Lord plays along).
But there is a high risk the Lord will take the event as an insult by threatening him and retaliate sooner or later.
So if the Lord cooperates, he would need to leave town immediately.
Or If the Lord doesn't cooperate, he would need to kill the lord, frame it on the informant and have the guard/soldier corroborate his story. (Or rinse, and repeat witnesses till someone corroborates).