OP didn't you already start a thread on this 3 months ago - https://pinside.com/pinball/forum/topic/is-gottlieb-s-gemini-really-worth-6300#post-4882511
And according to a few people, yes the game really is worth that much to the right person - https://pinside.com/pinball/forum/topic/gemini-listed-for-7500-obo-in-the-pinside-market#post-3424661
https://pinside.com/pinball/forum/topic/gottlieb-gemini-pinball-value/page/3#post-2977487