I read through the last 2 days of his chatlogs and didn't see anything that breaks the rules
If he's trying to annoy you through chat client muting him will also hide anything he types.
I suspect he might of vote abused you at least once but it's only a suspicion. If he is you can report that but we'll need a demo of what happened a little while before and leading up to the vote for evidence
Edit - I noticed you said something about racism in the other thread you made and mentioned other people. Racism is something we can do something about but I'll need their steam ID's so I can see their chats.