He has been on RM since June and has eight reviews (real or fake, I don't know), so he should know how to navigate the rate question by now. You can use terms like "donation" and "fee for your time only" with him in an attempt to make him comfortable with the $ question. Don't wait until the meeting to find out! Might want to say, after you find out the fee, that you don't want to talk money AT the meeting at all and confirm that you'll pay at the end of the meet.