Dragon Age Origins Ultimate Edition PC Registration Code is only 16 Characters and not 20, cannot install game.

You asked, you got the only answer possible: "Talk to the EA Game Advisors."

The AHQ Hero did their part, but we're all just fellow gamers, doin' the best we can.

Only thing you can do is go through the Help Center again. 

You might want to try the "Live Chat" option this time.