>is that walt wasn't in a position where he had to clear
>himself or skylar
>
>the case died with hank
>
>unless I'm missing something major here which is certainly
>possible

Walt Jr. called the police on him and it was clear to him that Skyler was going to turn against him as well since she was willing to slash him with the knife in anger for ***DEA agent*** and brother-in-law Hank's death. Plus he knew Marie told Skyler about Hank cornering him in the desert, so I'm guessing he knew Marie would be involved as well.

He was full aware of what was going on.