haven't seen a lot of buddhist resumes, but if all of that is accurate (I mean where he worked, etc.) and he seems to have been (and still is) in Thailand for some time, what is not credible?
I couldn't (and wouldn't) speculate on the timeline he gives, the way he met his teachers, the practice he's done etc. etc. - But in Christianity we had that old saying 'By their fruits ye shall know them..." which applies here IMO.
About the Map's discovery he offers:
The Tambolian Map Story
The information uncovered and the extraordinary range of the Tambolian Map is developed in the four books of the Bodhicariyan Paradox, or will be as soon as I can finish the manuscripts. How the Tambolian Map was actually discovered and became a reality is quite another story. I suspect it all started with me pilfering the Longchen Nyingtik Refuge Tree Visualization which is one of the stories I included in the Buddhist Humor book.
It's really hard to tell whether or not the "The Voyage of the Dream Maker", book one of the "The Bodhicaryian Paradox" is supposed to be taken as Terma, or just really bad sci-fi/fantasy, but my suspicion is that he is testing the waters and offering this as the former. At the end of the first offering (I read it pretty much all the way through out of morbid curiosity) he tells the reader to contact him if they want more... Or, maybe he just ran out of steam while writing that much, and needs some love and encouragement if he is to go back to the well and produce more of the same.
Perhaps this is a way to fish for disciples (at worst) or, (at best), test marketing for some bad sci-fi/fantasy.
I also have a really hard time with westerners, or anyone who go off the deep end as appears to be in this case. It seems as though nobody is immune - whether it's a lonely, frustrated, older (but very buff and handsome) writer, or someone with a Geshe's degree who professes their realization and decides to teach and lead others in spite of being told by their elders and lineage holders not to, or someone who has real potentiality and capacity who is taken under the wing of a genuine teacher, only to go out and start their own "thing" and "play rinpoche" ignoring their teacher and teaching w/o permission etc.
Based on the words of Longchenpa, this has been going on for at *least* 600 years... so I don't imagine that it's any more or less prevalent among westerners rather than, say, Tibetans or anyone else - I think it's human nature, and it is also a reflection of the real deal - why would someone fantasize about these kinds of things, if the cause wasn't already there, and if they didn't at least "feel after" the legitimate expression of the source of all things.
When I come across a "Three Face Palmer" (as someone so aptly put it) like this, I'm also reminded that in the ultimate sense, my own fantasies and forays into this or that, all of my grand schemes too, are like the games of children - never finished and in the end, silly distractions for the most part. They seem legit to me, and worthy in my eyes - but I suspect that in the end, my own plans and grand ideas aren't any less silly, or any less of a waste of time than someone who's plight is so obvious that I can't look away, like a train wreck.
So - May all of Yogi Yahi's good intentions and aspirations be fullfilled and may he and all beings be speedily brought to perfect realization in this very lifetime. And, in the words of the irrepressible Mike McDermott from Rounders "Like they teach you in One-L - Caveat Emptor, Pal"