Really? No pats on the back? No youdamans? Messa has a sad :-(
;-) Or did I not mention how difficult that shot was? ;-)
Well, anyway, I decided to change the approach to the cantina matte shot. The Dewback actually moves a little in the original (I checked in other sources, it's not one of those weird GOUT things where things move which shouldn't). So I recreated the matte from an SE snapshot and deleted the CG Dewback and superimposed the GOUT Dewback on top of the matte in movement.
This also required tracking the GOUT gate weave and applying it to the HD matte, so that the Dewback doesn't shake independently. But this should be quite acurate to the original appearance of the shot, which apparently had more gate weave than the other shots (quite possibly on purpose) because it has quite a lot of it even in DJ's stabilized footage.
I'll post the video as soon as it's uploaded.