So I will offer a guess as to what happened in this video that led to the panic. My guess is based on something I saw once myself.
Let's start by looking at what we see.
We see divers in cold water gear at the end of a dive--they are giving the thumb to begin the final ascent. Everyone seems to be fine, swimming calmly with neutral buoyancy. Suddenly we see one of the divers is significantly deeper than the rest, deeper by far than she was only a few seconds ago, and she is struggling to ascend, struggling, in fact, to stop her descent. Unable to do so, she panics.
Some years ago I had a student I had never met in in an AOW class. She had newly moved into our area, and this was her first time wearing a 7mm wet suit and hood. At the end of our first dive, I signaled the ascent, and she immediately raised her inflator hose, dumped all her air, and started to plummet into the depths. I caught her as quickly as I could.
When we got to the surface, I said, "Let me guess. Your OW instructor taught you that when it was time to ascend, you are supposed to dump all your air and swim up, right?" She said, "Yes, isn't that right?"
Many warm water instructors with students wearing 3mm suits with minimum compression at depth, teach that silliness.