The moment Salvador said about Mass Fusion Disposal Site, the misc quest came. And then nothing happened, Salvador stayed on top level, where the vertibird should strike us, but that didn't happen, so I took care of the misc quest, took that the place. And then returned where Salvador was, took me 15 min when he finally talked back, the vertibird flown above us, and completed the quest, and the flare gun also worked, when I took back the castle. So I don't know what went wrong, but it is solved, now I'm doing thee internal affairs, but flare grenade would be better it is silent too.