I had a similar experience once at DXB waiting on my flight to PEK. Sitting in the EK A lounge and watching the screens with all flights before and some after displaying some sort of gate status but nothing showing for the PEK departure.

I like to get to the gate early usually but as no update on the screens just sat about in the lounge as the boarding gate was literally just along the corridor and boarding from lounge level. At T -30 I buckled and wandered along to the gate (along with a few others) just as a last call for passengers came over the PA. I mentioned to the gate agent, as did another pax being dealt with by the other gate agent, that the FDS in the lounge was not displaying any status for our flight. They both apologized and as it turned out, we were the last 5 or 6 passengers they had been waiting on. Everyone else had boarded promptly.

Since then, I’m always at the gate early and if in a lounge will get a verbal confirmation in good time from the lounge agents.

S