There's some weirdness going on with the AUG reloads.
The AUG A3 has a last shot bolt hold open, and a rocker style bolt catch that works in a similar fashion to the AR-15 on the left side of the receiver above the mag well. But the animations don't seem to use it.
Instead one of the reloads uses the charging handle lock back to reload, H&K style. This isn't necessary, the lock open function on the charging handle is largely intended for administrative use and malfunction clearing. Plus, if reloading from an empty mag the bolt will already be locked to the rear, so there's really no point in doing this.
What exactly is going on with dropping the mag during the speed reload? Is our character reaching under the rifle to pull the mag release from above? That seems awkward as hell, I'm not even sure it's possible. Or did the animators think the bolt catch was some kind of secondary mag release? That would explain why it's not used to release the bolt in any of the animations... Either way, it's seriously weird, and I don't know why you'd do it that way.