How to decrypt the D.R.P. Mail Cypher message in Crysis-3?

I finished the game on normal difficulty, and noticed that somewhere along the way I picked up an encrypted message. It appears under Story Information / Messages as "[ENCRYPTED]: D.R.P. Mail Cypher". When you read it, game controller key sequences are displayed that you must enter in quick succession, but I'm never able to get them all in time. Is there any other way to decode this message? Was it tied to something in the game that I missed?

I just came across it and managed to crack the encryption button sequence and was able to open the letter. From what I can tell it looks like another code to crack, but i have no idea where to start.

This is what I see on the screen as best approximated in this window:

______________________________________________________________________________
                                 CORRESPONDENCES
______________________________________________________________________________

D.R.P. Mail
______________________________________________________________________________

-D.R.P. Mail                                                                 1

 M6                                                                 10.10.2010
 _____________________________________________________________________________

 rot hex rev rot 120234655564 15 142565543502N584N565D4R4N5