They should give you a refund! The star of the show has changed and you bought the tickets on the basis of seeing that star. If you bought the tickets through ticketmaster, they are giving refunds to any David fans that want to return their tickets. They sent out an email to those that bought C.C. tickets from them. Also each other theatre is giving refunds, so the albany one should as well. You should really hound the theatre about the refund.
Broadway theatres will refund tickets if the star is out of the production on the day you have tickets for.