Open your hood and look up on the back of the hood and see if there are not keys taped up there...When I bought my NH -TC-29D I had but one key...but I found 2 more taped on the underside of the hood of all places...
not sure about Deere or other brands, i woudl assume they are all the same, but when one of our new New Holland's come in new from the factory they have 2 keys with them, if it is a cab two for the door as well if they are different.......