I apologise in advance, having spent all day in hospital my patience is limited.
1) The modem config file names are
not encrypted, they are dynamically generated because...
2) The modem config files themselves are
not encrypted, they are cryptographically signed so that they can only be used on the modem that is to receive them. Obviously this requires a dynamic config name to avoid a modem downloading a file which is certified for another one....
So there you are, no encryption, dynamically generated and cryptographically signed config files.
Bad Moldova making stuff up about this mystical cable modem decryption chip!