Cool. I wonder if they’re counting their digital scans of the films? When I was there they were just getting Star Wars in the pipeline to be scanned on their 2k telecine. Not terribly long ago I saw a little article written by a guy who went to their viewing room at the library on capital hill and watched a copy of the scan of Star Wars, so we know that scan is finished. It wouldn’t surprise me if they’ve also completed a scan of ESB but havent gotten around to ROTJ yet. They prioritize their scanning based on historical significance as well as condition of film (i.e., how long they’ve got before it’s too badly deteriorated). SW and Empire were both significantly faded to red (ESB being the worst by a decent margin). Jedi still looked brand new.
Anyway, I’m not doubting what they told you, I’m just trying to figure out where these additional copies came from and exactly what they are. Because back in 2011 it was very clear they had one print each of the original cuts and one print each of the '97 SE.