After an hour in a queue with a full guild group, we finally managed to get past the ready check by doing a countdown (we have teamspeak) and pressing F on the ready check at the same time.
Haven't been able to re-test it, but if you can't get in, it's worth a try.
We noticed that the ready check was failing always on the second DD, so we thought if we all went in at the same time that might work. It did.
Favourite NPC: Wine-For-All
Mostly PC-EU , with a lonely little guy on NA.