Well, it is marked as rumour and I think it is just that, a rumour (although Commodore Managment fu**ed up other stuff as we know)
I mean, they obviously had allready Amiga Computers on the Set (they say so) and than have to buy another for demonstrating?
Unlikely. No imho the better explenation (and iirc this was also stated elswhere) might be the Scene itself where this computer
was to be demoed, Scotty says something along "What a keyboard? How antiquated!" (Note I've never seen the english original, but
I guess it was something like that

) and my guess is that Commodore simply didn't like the Idea to have their Flagship called
"antiquated"
BTW, in other areas, Commodore was quite cooperative, in some of those "Nasa interviews" it was said that one of the reasones
for the Engeniers going Amiga was that they simply got all neccesary documents for the hardware and such, thus making it
easier to modify the system (iirc the first 68020 for the A1000 actually was made by the NASA), while Apple did have no
interest to share their docs