“But he does good work.”
Some possibly useful advice: if I'm at a conference and someone I sort of know says, "This one speaker is being an ass.  He's pestering me about another speaker."  I'm like, "yeah, yeah that's part of being an organizer".<p>But if that person says, "Can you help me?  Bill Smith is harassing me."  Now they've got my attention.<p>In this case I don't know what the exact dialog was, but if you want help be sure to ask for it and state clearly why.  People will respond more proactively.