Just one comment: using the GreaseWeazle makes sense here, but other options would include seeking out the help of the community. For example, 5.25 inch floppy drives are widely available, and reading RX50 format on an ordinary drive in Linux is a trivial exercise. Similarly, feeding the recovered device image to a SIMH instance would be easy enough. The tricky task of translating the application data to readable text still remains in any of those approaches, of course.
This is an interesting case. I have done digital forensic work, and I would not stick such a disk in one of my RX50's in any case. A museum having a dedicated system with write hardware blocked and a drive that is known to not eat disks is the right way to go.
Kudos to System Source. It's good to be able to do this.
paul