For what it's worth, I do think the US government could corrupt academic cryptographers. If I was an academic cryptographer, and someone from the US government told me to do something immoral or else they would, say, kill my family, and they gave me reason to believe the threat was genuine, I'm not so sure I wouldn't have done what they told me. And I know this sounds like spy movie shit, but this is the US government.
One last thing though, if you're giving me the black and white choice between blindly trusting the outcome of a US government cryptography standard competition or distrusting the field of cryptography altogether, I choose the latter.
Note that the “forcing someone to comply” thing was just meant as one possibility among many, I don’t see why you completely dismiss the idea of someone who’s good at cryptography being in on the US’s mission to intercept people’s communications. I mean the NSA seems to be full of those kinds of people. You also dismiss the possibility that they just … picked the algorithm that they thought they could break after analysing it, with no participant being in on anything. But I get the feeling that you’re not really interested in engaging with this topic anymore, so I’ll leave it at that. It’s already late here.
Secrets are hard to keep at scale. Trying to do it with coercion, to a group of people who's entire field of study is covert communication, seems like an unenviable prospect.