Hey, it's not a stupid question. If I wanted a copy of a rare game, I wouldn't hesitate to consult people on a forum concerning said game.
Perhaps this person simply LIKES the Green Version better? Or they have a sentimental attachment to it, and would like to keep a working copy around for that reason? I'm like that with Harvest Moon GBC even though I find More Friends of Mineral Town to be a far superior game. I still like to be able to go to the utter simplicity of HMGBC to remind me that there were times when I didn't have that flashy "rucksack" or the fridge, shelf, marriage, etc.
I would still like to know at least the general condition of this fellow's (or lady's) game beyond "it's broken" so that we can determine if it can be salvaged before a purchase is necessary.