I don't think the children did lie Ana . This is very bizarre.
Firstly, why should an experienced Santa suddenly turn rogue? He's never done this before and presumably was ok for the rest of the day or there would have been more complaints.
Secondly, why should a waiter make those kind of remarks? Again out of character.
Thirdly we've only the mother's word that any such thing happened. We've not had a chance to discuss it with the actual alleged victims or to hear Santa's version of events.
Fourthly, who gave the 'story' to the press and what did she have to gain? A free visit to Santa as doubtless the store refunded her money (or perhaps not, is that why she went public?) and we know she got free meals at the restaurant.
What did Santa have to gain by acting out of character? Nothing..he lost his job.