If this hasn't already been answered, I MAY be able to help.
I had to get a MFT BEFORE I could even get a Class 3 medical. The issue is that I couldn't be cleared to Solo till I had my medical....a bit of a chicken or the egg thing. The FSDO assigned me to a specific DPE, that was also a CFI. (I needed a CFI because I wasn't even cleared to solo, let alone take passengers.) The DPE had to get checked out by my CFI in the plane I rented then I went up with the DPE.
The MFT was NOT to verify I could safely fly the plane. It was to verify that whatever my medical issue was (mine was monocular vision) was not prohibitive to my ability to fly. For my MFT, the DPE asked me questions about distances both on the ground and in the air. He helped me with the landing but I called out distances as I was trying to handle the landing. I passed because the distance judgements and my ability to see other airplanes were deemed acceptable...it was NOT a judgement of my quality as a pilot, only of my medical condition/fitness.
James