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I could be wrong but I believe that there was a TPMS change around that bin range, maybe the 21"s come with TPMS included thus they would need to know the vin.
No, the VINs are to delineate the TPMS sensor switch over from a Chinese brand (IIRC) to Continental's TPMS. Thus, if you want your TPMS to work, you must have the correct sensors for your VIN.
Good news: the current price for four new Continental TPMS sensors is only $200 ($50 each) plus tax; no idea what the older sensors cost.
p.s. Note that you'll also have a constant warning light if your TPMS isn't working . . .