I'm just tossing this idea out there, maybe get the machine over to Shonumi (reverse engineers unique and obscure GBC and GBA devices and functions, such as the GBC Infrared sensor, GBA MMBN Battle Chip Gate, and the Pokemon Crystal Mobile Adapter GB, among other things, all to add to their emulator, GBE+) or the REON Dev Team (they also work on the Mobile Adapter GB, adding support for the other games it had, trying to recreate the servers, I don't know if they work together) and maybe one of them can emulate the special GBA like hardware to allow the NR disc to actually transmit the event via the Dolphin emulator to GBA emulator connection feature. I think it was stated in the stream that the BIOS was dumped, but it was exactly the same as a standard GBA. So there must be some other hardware in there that has to be analysed and reverse engineered, which would likely take a long time. Obviously it would be up to the owner to contact these people and see if they're trustworthy of the equipment, but if no one else is working on the hardware, maybe let the owner know. Also, I don't know these people, for all I know they might not be interested in this, or not have the time.