On both occasions I heard two revive grenades on your video. On the first one he was obviously within the range, on the second one it's not so obvious, but it's highly likely. Correction, he stood up three times in the video. The first time you don't hear rezz grenade, but the green rezz effect is obvious above him. On the other two rezzes, you can hear the rezz grenades going off.
I think SOE needs to sort out LOS, AOE effects ETC. It's just too weird how some of the Grenades work.
I find all these claims of rez grenades odd since you don't once see another enemy player during the entire video. Unless this guy's got a personal medic hiding nearby throwing rez grenades just for him.
Look to your right on the ground as you go outside at about 21 seconds in and you'll see the first revive grenade on the ground. I'd guess it was probably multiple revive grenades thrown in the same area from a medic with grenade bandolier.
listen to the audio, there's another NC outside the door spotting the medics, you can also see the ress grenades just outside the door, doubt it's a hack.