I see this as a problem with a number of facets.
I don't think the current roster have any confidence in the coach or want to play under him. I expect their lackluster play to be an ongoing vote for replacing him.
I don't think that Muss likes what GP has given him as a roster.
I don't think that GP can like how Muss is utilizing his roster, contracts limit how much he can change it (in any positive direction), and the longer Muss keeps the team tanking, the more limited his trade/FA options are.
The obvious choice is to change coaches and re-evaluate, but Muss seems to be letting the Maloofs coach the team from afar, so they will probably have a hard time realizing that their revamping of management is a failure.
As for what trades GP might make before the deadline, I'm not even going to try and guess -- especially with the activist-owner wildcard thrown in.
What I am hoping will happen is that the Maloofs will let Muss continue tanking the team, then fire him the moment the season ends, and replace him with someone the players can get excited about. A great coach, and a great draft pick, would go a long way towards getting the team going again, and selling a fresh batch of season tickets.
I think that's the best we can hope for at this point, and I hope that the Maloofs have the presence of mind to do it.