Yeah, that was what I was thinking. It's probably also possible to cut the engine bit from the fused Windows version, but that sounds messy in comparison to extracting the .love from the OSX zip.
Getting that AppImage stuff to work is really not straight forward, so I don't blame you. Maybe I'll put up a guide once I managed myself. It kind of sucks to not have a Linux build that "just works" as developer working on Linux.
I wish you relaxing holidays!