A FlyerTalk Posting Legend
Join Date: Sep 2009
Location: Minneapolis: DL DM charter 2.3MM
Programs: A3*Gold, SPG Plat, HyattDiamond, MarriottPP, LHW exAccess, ICI, Raffles Amb, NW PE MM, TWA Gold MM
Posts: 102,617
Long before getting to the airport, you risk having one or both tickets/reservations cancelled due to the double booking.
If this is business travel, your employer should pay whatever fare is needed for the NYC trip. They should also pay the costs of having to change your approved vacation travel due to the business obligation.