Honestly, just destroy the card... That eliminates the license that may be tied to it and any chance of privacy concerns from the data.
It can easily be replaced by any Mitel vendor, the 1GB card is around $60 and the 2GB is $100 (MSRP) and will have a new SSL number, it could be tied to the old AMC record by the owning vendor or transferred to a new one and used with the new CF.