if u join first only u will get the exp
if there are lets say 5 ppl in server and u (the one that was getting exp ) leaves than.. ah... lets say the game pick one of those 4 randomly and they are next to get exp xD
dunno if u can somehow see what is your.. id or what ever makes someone get exp
that way maybe u can force your friend to get it
and btw u need to remove the count for how mayne players are joined (I said it all in the first topic) otherwise u won't get exp