Being familiar with Ayer from his Epistemology works, this writeup was unexpected. How could an empiricist write "My recent experiences have slightly weakened my conviction that my genuine death, which is due fairly soon, will be the end of me". It also directly contradicted his stance about metaphycal claims.
Clearly he wrote it as an intellectually honest response to something he experienced, which is the very least expected of an empiricist and therefore consistent with the practice; implied contradictions are opportunities for further reflection and investigation, certainly not reasons to immediately reject the evidence.
An empiricist could write that with no contradiction if he experienced it, which Ayer did.
I think his conclusion is very reasonable. It's highly likely that NDEs are minds sputtering to a stop. But if you experience one (while your heart has stopped for 4 minutes no less), it seems rational to "slightly" update your priors towards the possibility of some kind of afterlife. At the very least, it may indicate some kind of conscious experience after you're "dead" but before your brain significantly degrades.
That aside, I will say that his experience sounds a lot like a DMT trip. Particularly the sense that "space, like a badly fitting jigsaw puzzle, was slightly out of joint" and the feeling of being in the presence of "the government of the universe".