It's not like I don't believe you, neither trust you, but it's not enough.
I'm not protecting anyone.
Giving your chatlog is a good thing, but still, doesn t proove anything.
Take a screenshot, when that guy actually hosted the game (yes, that precise moment).
Since you didn't leave the room yet, it won't be a problem (same for the other post).
Screenshots are much better evidences than text files.