It's not a bug, you just haven't completed it yet.
After finding his body in the Conex, you'll notice that only 1 out of 2 phases for Sandoval (Boss Map) have been completed. Just before the final Sueno mission, Sueno himself will contact you and direct you to an audio recording of Sandoval's interrogation confession. After securing that, playing it, and some banter, both phases will have been completed.
Check your boss map. You still have amber at 107%, right? If Sandoval hasn't been blotted out, place your cursor over Sandoval and right-click (on PC). That will bring up his mission menu. If I'm understanding your situation correctly, you should still have one mission left. If so, left-click on it.
Even though I'm usually pretty good at avoiding rockets in a heli anymore, if I were playing GM I definitely would fly low along rivers and pretty much avoid most areas with SAMs. I would instead fast travel when in areas with lots of SAMs. I know that's not as realistic obviously, but you can really only play this kind of game so realistic anyway.
Even if there wasn't a no revive bug, it's still very possible a heli will catch fire after being shot down and cause it to explode before you get revived, so it's risky either way.