So I tried queuing for a random dungeon with my level 70 shaman team. The levels for nexus are listed at 69-80. When I queue with 4 70's and 1 80, I get the message that "One or more party members do not meet the requirements for the chosen dungeons".

Is the 80 too high? Are my shaman not geared enough? Are they just too far apart in level?

All my shaman can queue individually.

Regular Nexus is rated as green, and the yellow dungeons don't start until Gundrak at level 74.

Anyone know the rules that I'm stumbling into?