Maybe Saul advises him to take a trip to Belize.
I see where you're coming from, but if he's disappeared, with all the blood likely all over that Nazi camp, I'd bet they assume he's dead and Walt came back to avenge him. Plenty of federal fugitives evade detection for long stretches.
, he's got such a conscience, he probably did something for his sweetheart's kid, Brock.
Maybe he stashed money. He collected tons with Mike. Probably knows of some great locations to hide it.
I mean, there's a reason cold cases exist.