Christie's Auction House Edward Dolman, CEO admits they've owed us $30,000.00 since Nov 25 but his staff won't remit it Internet

Last year we gave about $70k in Jewelry to Cristina Schublein, who used to work at Christie's.  In October $30k of the jewelry sold at auction and we received several communications citing Nov 25th as our settlement date, the date that Christie's said they would cut and send our funds.  Cristina apparently no longer works there, as none of the employees with whom I spoke could find her in their system.  Likewise they can not find my wife (the consignor) in their system.  It has been over 2 months since the settlement date and they're still holding our money.  The CEO Ed Dolman sent us a letter of apology several weeks ago by FedEx, bereft of payment, which was obviously insincere because he has had several weeks to rectify the situation, and no one in his organization, from Raoul Karakian, who runs the Jewelry department, to their PR lead Toby to their Legal staff to their secretary pool - with all of whom I spoke - will even acknowledge that we gave them the parcel.  I told them that they're leaving me no recourse but to sue, and their attorney Wendy Battle(something) and jeweler Raoul Karakian literally and explicitly invited me to sue.  So they'll pay my $30k and legal fees, but the public should be aware of their terrible customer service, professional ineptitude and disorganization.