Iv'e been messing around with a couple of keyvaults with known cpu keys. im in the same boat as you here a console and no drive key or cpu..8955

360 Flash Tool 0.91
(Insert cpu key as dvd key) (Self Encrypted/Decrypted CPU Key?)
CPU D2250EA2C6197597DE489DEA379CA098 <> CPUDVD B432B68FB8FF96A1BBBB13EB4A4721B2
(Decrypted DVD) (Encrypted DVD)
DVD 470ABA0C5CEE4EF25314CF7F5336FA25 <> DVD 211D02212208ADC436E7417E2EED7B0F
Whats interesting is that the decrypted/encrypted keys work viceversa. the nand is a lock and i dont have a key all i know about my 8955 image is this
00000000000000000000000000000000 CPU KEY
00000000000000000000000000000000 DVD KEY
B342FC830993CFE7D0A7C5D37325128F DVD ENCRYPTED