Have you done all the quests from him besides demogorgon? I was able to get the dailies after I completed the skirmishes and other quests from him. (Did have to wait for the 3am reset)
I am having the same issue when queueing for dungeons or skirmishes over the past couple days. I get in and then am not part of the group. So far for me I have always recieved rewards for the dungeon or skirmish but I am not part of the group.