So the TPS is a unit that can be removed and replaced (or in this case, fall off) so easily? Huh.
Interestingly, your description sounds exactly like my bike's symptoms when the battery cable lug broke, including, at the end, the MIL staying on. It didn't stay on for long, though, as everything finally died for good about a minute later. When I chucked the broken lead, and screwed the bare twisted copper wire right to the battery terminal, the bike ran fine, and the MIL was back to working normally. I never tried to read a code off it to see what it said, if anything.
Interesting that RE claims they insisted on the owner-diagnostic feature of being able to check the code, but apparently they didn't provide a way for the owner to reset the light once a problem is solved? Does this mean that even if you solve your problem, the light stays on until some authorized entity resets it?
As I understand it, if the ECU logs multiple simultaneous faults, the next one will be indicated once you rectify the first one, etc., so maybe if you check the code again you'll find another "problem"... ??