Ouch. When I had my warranty return, the vendor handled it for me and I didn't have to ship anything back. Magura asked for pics and then shipped parts directly to me. My online reseller was a Magura dealer and they handled the entire process (relaying the ask for pics, forwarding them to Magura etc.). Unfortunately it looks like you got a bad vendor.
I would definitely try to contact Magura. What have you got to lose, right?
Also, I use Wolf Tooth Fat Paw and Mega Fat Paw grips, wrapped in silicone tape (not yet in this pic). But like their name implies, you need large hands for them to work. I do not need glove padding and ride with just leather full finger deerskin work gloves.
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