Reseting a Gypsy - maybe there is a third way

Since PC is able to repair the G's my guess is that there is a 3rd way (or even 4th way) to reset . But maybe that reset is a full reset and erases all cartridge data along with the code writing capability which makes the G recognize and not link previously linked cartridge. PC wouldn't want us to do that would they so we are stuck with the 2  resets and not able to unfreeze some G's
Hmm....