I'm beginning to suspect this is going to last until the trade deadline where someone will cave and the Raiders will have to agree to take most of the remaing salary for a 3rd and the receiving team will have to hope he will agree to a new deal in the off season or release him.
Pretty much. He's either staying with the Raiders and getting cut at the end of the season or whenever that deadline hits, or he gets traded on a rental and the new team takes their chances negotiating a new contract or cut him after this season.
He's certainly not gonna get paid his remaining non-guaranteed contract beyond this season.
And while it would be nice to have him, only for the right price and circumstances. As you rightfully pointed out, his current contract is irrelevant beyond this season.