Atrax reminded me of the 64K cartridge with EA and Memo Processor in it. I don't remember how I dumped it, but pictures of it are here:
I think there was a bank switch or something that I did before I dumped each 32K memory space.
The only thing I can guess is that when Mechatronics built this cart, they did something with the paging bit (we'd have to check with JGardner on VCFed) and that RUN MP switches it to the 32K of the cart with Memo Processor and RUN ALDS switches it to the 32K of the cart with Editor Assembler.
I *think* how I dumped it is that I switched each 32K to the appropriate side by running the command for MP or EA and then exited back to BASIC and did a PEEK. It stayed in the bank of the last run program.
Also, maybe check with HAP who wrote the MESS emulation for it, because it's supposed to work as a 64K bank switched cart there.
Ksarul is in possession of this cartridge now, and can map where the A15 line went to.