Do your own key. It's not like you are going to get same dungeon for 8 times, right?
I mean you are talking like joining someones group is the only thing possible in WoW.
Join a community
Join a group
Join a guild
Assemble your own pugs
Suggest people to do some more keys after successful run.
Current situation is very simple supply and demand situation. It's very easy to find people to play with if you actually want to do something instead of acting like you are entitled to pugs you wish to join. Also know as - people who actually do something instead of complaining.