your car does NOT have actual hardware in the tires or the fender/wheel wells... the only hardware piece is different version of the center switch (module A169), that has the TPMS button (some have heated seats, all have Hill Descent, trunk, some have PDC). If all "buttons" are utilized, you only have one spot left... anyways, the tire pressure readings are taken in the software/firmware of the ABS module, that all the cars are equipped with.

the corrosion that they are referring to is for the actual sender units and to be honest, i am not sure that even if you had the RDCs, they would be able to replace the stems on the senders... you do not have pressure hardware in your car and they are mistaken - not to discount some aftermarket devices that the previous owner may have installed...