Cavanaughs Rittenhouse They canceled our event 2 weeks prior b.c they didn't realize they booked it during a big sporting event Philadelphia, Pennsylvania

I've had my charities big Halloween benefit scheduled for October 30th at Cavanaugh's Rittenhouse for well over 2 months now.  I called all weekend (2 weeks prior to the event) to finalize last minute details as we already have almost 100 tickets sold to this benefit.  I get a call today saying from the GM Maureen saying Bobby the old GM is no longer there and they see there is an event booked for our party in 2 weeks and they are sorry they can't honor it anymore b.c there is a world series game that night.