The only thing I have to say is that I think the GOUT is the key to finding out what TESB is supposed to look like. When I found a nice color correction for ANH and applied those settings to ROTJ, it came out very close to the grindhouse ROTJ scan. So I’m assuming that if you have a correction for ANH that works for ROTJ, that using that on the GOUT for TESB will get you something close to the real colors. Enough to guide a shot by shot regrade and possibly provide a basic correction that works for most scenes.
It sounds to me that Poita’s 35mm scan that has been in cold storage has the best chance of giving us an accurate representation of the color, without the guesswork of GOUT or anything else.