Cons should have a Standard Operating Procedure made known to all, perhaps someone designated as liaison to the local civil security authorities. They should be of appropriate manner and bearing for the locality to maximise the likelihood that said security services will automatically consider them credible interlocutors (the Designated Suit, if you will). Then if this sort of thing happens, the victim knows to complain to liaison, liaison knows to summon police, perpetrator is at the very least, severely embarrassed, if not, as would be ideal, prosecuted. Rather like the shops that announce that all shoplifters will automatically be handed over to the police.

This would also reduce embarrassment for the con, since otherwise,as will inevitably happen, some future victim will take the initiative and call the police directly without bothering to go through either con or hotel.