There is a problem of CTD with the panel and the current version of Orbiter,
it seem to me this should be the case here while you have two DGIII+3 EVA (5 big panel).
You the first one to report that but logicaly it should be the same bug.
I flown the mission lately and had the same bug than you: impossible
to start the RCS on the strangled DGIII, after quitting and relaunching
Orbiter with the saved scenario I was able anyway to start them....
This is also a feature .. sorry a bug

Dan