There is green shift on the 70mm film cells that were sold around in the mid-90s, but I have a theory that they might have made a new 70mm blowup off of an IB print (perhaps George’s print?) just to produce the cells. (Remember, this was right around the time they were going into the vaults and finding that the negatives for the first movie were in dire condition.)
The ESB cells have printed-in negative black edges (in the inner half of the area between the sprocket holes and the edge, which would be the edge of a 65mm negative) with blue Eastman codes for 1979. but brown positive edge codes of about 1995 for the actual print stock, on the outside of the edge (in the extra 2.5mm on each side of 70mm compared to 65mm), seeming to indicate the cells were newly printed off of original 65mm internegatives.
Meanwhile, the ROTJ cells seem to come from two original prints - most of the cells come from a faded original print (with brown 1982 edge code for the print itself), while cells from the last reel or two aren’t faded and come from an original LPP (also 1982 stock edge code, but actually says “EASTMAN LPP” - I found one frame that shows that portion of the edge code).
On the other hand, ANH only has the 1995 LPP edge code of the actual 70mm positive stock itself, nothing looks to be printed in from a previous large-format generation. Since these weren’t intended to be projected, they might have been able to cheat by duping from an IB print, and that would explain the green shift.