Create your disk just like you have. Then put that disk into a computer that does have internet access (surely someone in the bank has internet access, otherwise, how would you be posting here). Download the FFIEC software onto that computer, import the data from your disk, create the encrypted file and e-mail it to the FRB submission e-mail address.
Jim Bedsole, CRCM, CBA, CFSA, CAFP
My posts - my opinions