Jack - I am confused as to what it is you are disputing.
Was the information he provided incorrect? Were you damaged in some way?
Any known information regarding a property must , or at least, should, be disclosed.
If your agent is now working as your listing agent, and he has valid information about the home , he has a duty to disclose it.......why did you not want the disclosure to be made?
What is it you want to arbitrate ? If the agent used incorrect information, that's one thing.
I don't see how any actions you take against your agent will delay the closing - if you are involved in withholding information, however, that might be something your buyer will want to look into.
Obviously, there is missing information here, so it's difficult to comment any further.