My material explanation is that his traumatised mind was working overtime. Lights and meetings with Jesus are nothing exceptional and can all be explained rationally. It is the work of a damaged mind working overtime, there is nothing spiritual about it. I'm sure he believes it was real and justifies his current existence using it, but it is false.

Most people in accidents don't appear to meet god. and that is because noone actually does so. Utter bollocks and complete self delusion.