Oh, wait, that guy was Michael Moore, so it must be a Republican conspiracy against him! Don't they understand that Micheal Moore doesn't have to do paperwork? He has a special pass!
More seriously, to me, this sounds like an obvious publicity stunt.
I find myself asking "Why on earth would a multimillionaire take ten people who got sick cleaning up after 9-11 to Cuba for treatment?"
"Because it would be great publicity and he could use the opportunity to make sweeping statements about US healthcare (see how cheap third world healthcare is?) and at the same time make it very likely he would get in trouble and be able to claim he's a guy worth conspiring against" is the only reasonable answer I can think of.
who doesn't want third world healthcare, no matter how good Moore makes it look for the purposes of his movie.