If you wanna do Wolves' Den right now you'll probably have to organize your own 4v4s. Make sure the ranks of each team even out or you'll be waiting a while.

Since nobody else is in the solo queue right now it might be fun to go in with 8 people and see what teams it throws you in with. It'd definitely be worth it to bang out your 10 matches/3 wins for the week if you're high rank - for me I'd get over 2000 exp just for doing the challenge logs.