The “mariner involved” probably isn’t going to make an issue of this inspection with the CO of Coast Guard Station Cape Charles. It would be his (and three other crewmembers’) version of the event versus the boarding officer and his crew’s account. What good would come of a pissing contest? More boardings? Harrassment?
When an ordinary citizen, or in this case, mariner, calls a government agency out (especially a Homeland Security Agency organization), who’s going to prevail? It would be like trying to oppose the SS in Germany in 1940. All the government has to do is use “security” or “terrorist” in a sentence and they’re justified in whatever they do.
Unless you’re ready to pay the price, compliance and avoidance are probably the safest course to set.
Sorry to sound so dismal.
Nemo