Eh... The prosecution claims, and the judge believes, that they have a list of files they expect to find on the drive. If he gives them a password and those files don't appear, the judge will conclude he gave them the wrong password, and he will stay put until the right password is produced.

So you mean, if he floats, he's a witch, and they burn him, and if he sinks, he's innocent but he drowns?

That's not how this works. With deniable encryption, it is entirely possible that there doesn't even exist a hidden volume to find. They will be unable to prove he has a hidden volume and surely a judge will not compel him for not producing something he may not be able to at all.

Check out, for example, the case of Martin Armstrong, held for 7 years in contempt of court for not producing items he said he didn't have. Eventually he had to enter a plea agreement and serve an additional 5-year term.

Here is another project that is quite simple and works pretty well: https://github.com/dolanor/scubed

You can get this from VeraCrypt (https://www.veracrypt.fr/en/Home.html)

I got the impression that VeraCrypt was not being run very well and that the developers didn't have much security experience based on the audit report that came out. I didn't consider it a trustworthy project. Has anything changed that?

Isn't TrueCrypt 7.1a still reliable?

Yeah, it works well enough - some pain, have to deactivate it to do the major updates and such on Win10, but it does work.