Ugh, that sucks, but not completely surprising. I poked a teensy whole in MAD’s offering, Single MAD motor - #23 by kubark42, but your testing blows it wide open. So sorry about the wasted time and money.
I love your ambition in this project, and am looking forward to the results. Are you looking to create a self-launching PW5? Keeping weight down in an FES-style glider application is so much more important than in PPG, and so if the PW5 is your primary target I’m even more excited to see what the results will be.
P.S. One thing that makes LMT motors so good is that they use a press to compact the windings in order to cram more copper in. I don’t know if the claimed increase of packing factor of ~40% is true, but in any case it can only do good. I wonder how easily a DIY person could compact the coils? Maybe with vacuum instead of a hydraulic press?