Parts 1 and 2 deal with the events themselves, and you should read them. It is Part 3 that is of interest here. Although, in my opinion, he does not establish his case that bigfoot is not a flesh and blood animal, he does recount in detail his own psychical experiences in the Canyon. He then branches off into speculations about the nature of reality which need not concern us.
Normally, I would be reluctant to copy large sections of another's website, but I fear that, in this case, the remarkable story will be lost in the voluminous amount of information present on the Bigfoot Encounters site. (I really would suggest you read it, if you are interested in the subject.) Also, fair's fair. I haven't complained that the site includes a copy of a paper of mine from 1989, even though it represents an opinion I know longer hold. With this in mind, let us see what Mr Beck had to say.