Ie. The system is either in secure mode (with all necessary crypto keys for operation), or it is in insecure mode with a root shell open for debugging and failure analysis, but that transition also deleted the critical private keys.
Now I am curious if I can find a terminal myself, if they are actually getting phased out it might not be too difficult to find a used one...
What keys would you flash them with? Anything encrypted with your "new" keys can't be decrypted on the other end of the transaction anyway, so what would be the point?
Plus I meant for the manufacturer to "repair" it. Maybe tamperproof gets triggered if you accidentally drop the device in an unfortunate way