Of course it is. We've got (at least) Truro finding multiple species of wood and OITC finding cement, wood, iron filings, etc. at or above the depths where Bowdoin says he found nothing, all using the same basic technology of enclosed auger drills. Data for and data against. You have picked a favorite and you are running with it, but why?
If I'm following your reasoning correctly -- and maybe I'm not -- there is a thread of deceit running through the Team Yes camp going all the way back in history to the initial dig in the Money Pit spot. So they are bad. And the Team No camp is all righteous and good, and incapable of exaggeration or misdirection? Aye? So you are Team No all the way, because of their Light. And when H.L. Bowdoin starts out as Team Yes, but then switches allegiances to Team No, you support him all the way, no questions asked. And no questions answered either, apparently, including my uncomfortable one about why he wanted to continue looking if he supposed there was nothing there.
I don't specifically recall but I'll assume that, like many facets of the search strategy on that show, it was built up to be a Thing and then frustratingly left to drop. I don't see how that's relevant to Bowdoin's "proof".
You seem to have placed great emphasis on this notion of the map which may or may not have started it all, and the idea that because it's no longer spoken of it somehow casts shade on every endeavour of Team Yes. Whereas I don't see how it makes a bit of difference why they chose the spot they did, only what they find once they get there. Some of the news reports from the old days mention the map, some don't. I don't care. Why do you?
Clearly if I'm quoting to you from outside sources then I'm not relying on the show to be the font of all wisdom for this topic. Let's face it, the show presents a simplified version to match the attention span of the average TV viewer.
Okay, so now comes that pesky conspiratorial thinking that seems to infect you Team No guys. Now the plot extends to include third parties like D'Arcy O'Connor, eh? So never mind that O'Connor is largely quoting from Blair and Chappell's own journals and correspondences, and the men themselves in interviews, but he is distorting the account of what they found? So that it's no longer data but just a fabricated story? And when other authors reach the same conclusions from the same sources, I guess they are part of the plot as well? And that's why Bowdoin wins? Weak man, very weak.
I suppose you have curated a list of authors pure enough for me to rely on, then? Well by all means, out with it, don't leave us in suspense. Also, please cite the sources you pull your quotation screencaps from. I've asked for that before without, I believe, a response.
--GT