Been playing through to catch an orc, I haven't had any success. Seems like playing two player we get land swamped because mugash never turns up, he is consistently near the bottom of my or my partner's out of play deck.

Given we have been playing leadership and tactics decks, but come on!

Try Glorfindel+Asfaloth, they clear locations and include spirit for threat reduction

I agree, my wife and I have never managed to win this quest 2player. I don't know what your exact situation is, but I have base game, VoI and FoS. I am using Glorfindel (spirit) and Asfaloth, and it doesn't help much. Like you, we get overrun with locations, then Broken Lands comes up making Asfaloth a lot less useful, and Northern Tracker a total waste of time. There's so much threat in the staging area that we just can't win at questing, or not by enough. I am even using Eowyn. It only takes one or two turns of unsuccessful questing and then the Time effect goes off and there is pretty much no way to recover. I'm really struggling with this quest.

Just had a great solo game with Hobbits (Sam,Pippin,Merry). Beat it first try!
Also Caldara deck is good against this quest.

I initially beat it with Glorfindel/Frodo/Legolas.

High willpower and high attack seem to be the most important things to have.