I don't think the code to access the engineering menu is in the wold just yet. Once MB realized that we mere mortals had access they took it away as quickly as they could.
I've even lost access on my 06 now that the firmware was updated on COMAND at the last annual service. Not a typical item covered but I wanted the time to destination in navigation to work and foolishly asked for the update. Oh well, live an learn.
Sorry I didn't have the info but I didn't want you to think everyone was just ignoring you.
Some Car Audio specialists have the software on laptops to get into the Engineering menus on cars post 2006 onwards - I had my DVD region code unlocked and the TV "on the go" activated for £150 in the UK - took the chap 5 mins to do