DICE LA Camo Easter Egg help needed

So I've gone through the process of joining unranked server, getting all 20 lanterns to light, heard the audible 2 beep confirmation upon the last button being pushed.  I then went to the keypad adjacent from the skull in the temple and entered the code, 8398-08-0000 and I'm getting a buzz instead of the second audible 2 beep confirmation and new morse code.  All I'm getting now is the same morse code telling me about the "when night falls over the old factory........"  I am unable to interact with any of the 7 buttons now too.  WHAT AM I MISSING ?  

Thanks in advance for your help.