Yeah, I've been saying this a lot over the past couple days. Even without any other customizations, simply a die shrink to 16nm while retaining Maxwell architecture might appear to be Pascal based to some people. Which is certainly how your sources may have heard Pascal.
Their spreadsheet only says anything about clock speeds. They base the rest of their speculation on the "leak" from the OP of this thread, and say that developers have told them that it is close to what Nintendo is telling them to expect. Close in what way, no one knows.
Based on benchmarks linked here it runs at max clocks for a decent period of time without throttling and with passive cooling only, though I have no idea how hot it gets. But the clocks for the Switch are even lower for portable- much lower- which means there should be absolutely no way the Switch requires active cooling in portable mode. I think a poster said the Switch, with these clocks, will have the same TDP as the Vita but a far bigger surface area.
When docked it's looking at about the same clock rate as the Pixel C, yet doesn't have to run on battery. So even docked it doesn't make much sense to require a fan. Let alone two fans, potentially.