NDE is much like or part of what Japanese Buddhists called satori. It is knowing, an experience, an understanding that as far as I know cannot be adequately explained. It must be experienced to be understood.
Once years ago I had a very strange experience though it was not an NDE. I think I might have a smidgen of understanding as to how NDEs exist and WHY they cannot be adequately explained in human language, which beyond the material world is limited.
I knew next to nothing of Buddhism at the time. The experience was most certainly real as is the understanding I gained. What I do know is the knowledge I gained came in being, not in explanation or language; just being in the experience. As result of the brief and completely unexpected event I know a few things that I cannot adequately explain.
Briefly I will give it a shot, which will be unsatisfactory to everyone. It's not in the telling. It is in the knowing and I cannot produce such an experience. In fact, as of yet I am unable to replicate it even for myself.
We are truly one with everything. I have experienced that. I can tell you that and brilliant minds may tell you that but you cannot comprehend it because you have yet to experience it.
Animals, water, the wind, all living things, all things are ONE. It is a knowing, a feeling or a being beyond explanation. It is a feeling of complete peace, freedom and love (I suppose). But those words, like trying to explain an NDE, in no way give you the knowledge. I understand why many or most people cannot accept it.