Really strange this. Here in holland you can also fight against people in a weightclass one above or one under (thus a lot of kg difference is possible) BUT you're not allowed to step in the ring without your trainer or a licences match-trainer appointed to you by your own trainer. What's also strange, is that the trainer must have known who the opponant of your mate was, and must have known his weight. At least approx. (given that the opponants' trainer has been truthfully on the forehand).

Strange cause of events, this is. Best of luck with your mate!