I can only relay my own experience which was sending him the following message to his text message number on RM.
“Hey Jack, found your ad on RM, my name is [Redacted]. I'm wondering what times you are available on October 7th.
Thank you. “
He responded 6 hours later on the same day. We eventually agreed on the night of October 6th in Atlanta, and saw him 3 hours after he flew in. He did tell me he only considers this a part-time job, so I have no idea if that has any influence on if he responds or not. I’m sorry that he hasn’t been responding to you but maybe my response to you can help in some way.