I do have the old ones, they are still mounted in the old wheels with old tires in storage. They were all working when they cam off a few months ago. Discount said that they wouldn't need the old ones to program the new ones (even more suspicious).

They did say that installing standard stems in TPMS systems wasn't allowed due to liablity and insurance. This is in addition to them not touching my care because of the spacers required for the wheels that I chose.