Regarding lucid dreams, it is mistake to conclude that they aren't a good source of information because one has received information from such a dream that couldn't be verified, because some people receive information from lucid dreams that can be verified. It is a matter of the circumstances that are in play and what a person needs.

I've found that most of my dreams, whether lucid or regular, serve the purpose of helping me learn from them.  There are clues within the dreams that let me know that they are created by some form of love-based guidance.

Once a person understands that he (or she) can receive information this way, he is more likely to receive it.

Some say deceptive beings can create dream experiences for people. I don't know to what extent this is true. If one closely considers what takes place within one's dreams, one can determine if they have a friendly source.

Regarding why some NDEs seem more dogmatic than others, I believe it is partly a matter of what a person is open to, and partly a matter of what his (or her) audience is open to. Consider Howard Storm. When he speaks to a Christian group he sounds quite Christian. But listen to how he speaks to a non-Christian group.

On youtube check out the three part video called, "Rare Near Death Experience Interview with Howard Storm" . There are three parts.
Albert