We saw this on our first attempt. I think it's a delayed reaction to not having taken his shield down quite quickly enough. But it sure is annoying.

So, can anyone tell me what’s going on here? Why am I getting bounced up over that nice little barrier?

I'm always on the "away" team for that encounter and I've seen that happen a lot. Your view does the slightest jiggle before you hop over, so I'm wondering if your teammate bumped into you. No radar in there makes that idea impossible to verify, though. My other thought is that you appeared to be right on this edge between tiles, and you might have gotten popped upward just the slightest bit when transitioning between them:

We've also had just one of us get pulled forward early, like somehow the barrier fails for just one person. It hasn't been an issue as long as the "home" team is fast enough, but it definitely happens from time to time.

This was happening with a frustrating frequency to our "away" fireteam. It would happen not just from this location, but on any barrier, even ones that were more flat than that one (that was the one I bothered recording). I don't think Cody or Vortech bumped me, I turned around after flying away, you can see that they're both on the opposite side.

Perhaps it was because I bumped into that slightly raised tile, but I've stood on that raised tile before w/o a problem... I dunno.

Anyway, I just had to share that for the home team to see.

Can someone explain this part to me?

During the Calus fight, there is the segment where the "home" team stands in the warlock buff zone and the floor is lava. The multiplier goes up. Then Guardian tells me to take down Calus' shields. What exactly is happening then? What affects the multiplier going up? Am I not supposed to shoot the shields before that ???

During that portion, the Away team (Dark blue world with giant head) is shooting skulls that fly out of Calus's mouth (it doesn't make sense in context either). Each skull destroyed is a damage stack, and the goal is to get as much of a multiplier as possible before the timer runs out.

The Home team outside in the Throne room is directly in control of how much time the people inside have. Once Calus's shields are popped, the time is up. The entire time that this is happening, Calus starts building a charge that turns the entire room into a microwave, so unless you're inside a Healing Rift, you're continuously taking damage. The goal is to give the Away team as much time as possible to shoot the skulls, but if you wait too long, Calus will finish charging his attack, and he'll wipe the whole team.

Once his shields are popped, the multiplier stops building, and teleportation orbs appear for the Away team to use to come back into the Throne room with the damage stacks that they built.