I hope it does sell for six figures but i am thinking it would sell for between $xx and low $xxx.
it has been a long time since anyone has paid six figures for a dot mobi,
Dont get me wrong i own a few great dot mobi names and if that one sold for six figures I would be exstatic, but I think whoever you are talking to is either lying to you or has no idea what a domain name is worth.
Good luck.