The timed pyrotechnic is too complicated. To really throw them off all he had to do is take off the tags or swap them with another vehicle and leave the truck in a parking lot. It would be days before it was found by which time he could be hundreds of miles away. But I don’t think he is running. It is more of a cat and mouse game. He wants to kill again and he wants to do it close to LA.
I think you are right. He has already counted himself as dead. He's trying to take as many as possible with him.