Yes, I believe there's a good chance Tormund has already died at that time the wall fell down. :)
You know, tv show mostly continued from where it left with it's last scene in last episode. And I think the aftermath is probably the first thing they're going to show with the opening of Season Eight.
According to this image, the wall by the EastWatch is destroyed, whole wight army has passed through it. Maybe one or two wights lingering around before joining the rest. And then we see a movement beneath the snow. A hand appears, and then the whole body comes out between snowy ice blocks. Seeing his back, we immediately realize it's Tormund. He looks like he is devastated, his shoulders are down. He stumbles a couple of steps towards the wights which passed the wall just recently. Then camera pans and shows his face and his eyes... And the opening rolls with iconic main title theme ! ;)
Let's wait and see what is really happening on tv.
Valar Morghulis everyone!