MM told me to only pay $50 for a hh session.Have you ever got a discount/refund?

http://shopnix.in/images/shopnix-refund-guarantee.jpg About 2 months ago I went hunting and the session was pretty good at the beginning but below average near the end.  I didn't complete my shot and time ran out.  The mm did something to destroy the mood or wreck the feel of the session half way thru the session.  She was aware of this and at the end of the session when i wanted to giver her her full donation, she said that she doesn't want it all and to only give her 50.00. It was my frist time seeing her and I had no plans to repeat anyways. I'm sure she didn't give me 90 back as a reverse tip for my pse service i provided her Wanted to know if this has every happened to any of you bros? and what was the situation? http://shopnix.in/images/shopnix-refund-guarantee.jpg