I hadn't heard if all of the session tapes for ROTJ had been found but I know that at the time of the SE's being made... they had no time for one, and for two had poor masters... and so what we got was a pretty sad set.
Not to mention they cut music no longer heard in the film like the original finale music and the Lapti Nek. THe music didn't fit for one, was no longer used for two, and couldn't be located for three...
My sets I hope improve upon this... I'm gonna push my luck and see if I can't upload them all back on the site agian.