Here's the problem: most open source software isn't owned by US authors. So the software is developed and maintained with absolutely no concern about anal-retentive American military "requirements." You can hardly take a global project and demand that people from certain nations stop contributing so that you can ship the software to a US market without getting into trouble for "conspiring" with those nations.
Quite frankly, the law is asinine anyhow. There are no shortage of places around the globe to download and access the full code and binaries of "restricted" software from those nations, because there are other nations who participate in open source projects that don't kiss American ass.
So as far as I'm concerned, RedHat is doing what is necessary to continue using open source software.
To truly meet the American legal requirements, they'd have to rewrite and lock down an insane amount of software -- including replacing the Linux kernel.