That agent will be getting his/her part of the contract monies. If you hire another agent there would be a conflict.
I would recommend you speak with Broker of record or manager about your problem.
No. the agent is procuring cause and brought you to this state of the transaction. You can call the broker and ask for another agent to do the tasks associated with the rest of the closing, it is a thought but really at this stage you can just work thru the attorney.
What is the issue? Hard to think at this stage you want to fire your Realtor.