I reviewed episodes 9 and 10, and they are well thought through and well done.
In my opinion, and based of killer instances of foot entrapment where I had access to the facts, we should think and worry more about those where the victim catches a foot or leg, and then is forced over so that he can't raise his head to breathe, and may not even be visible to potential rescuers. That was my situation. I could barely get one hand above the water surface, and no one in my party saw my hand.
In such a situation, getting a rope to the victim to help him get higher to breathe may not be an option. Usually it will be necessary for someone to swim down from above, without delay, and risk their own feet and legs to try and extricate the victim. Shuffling out from the bank to the victim in the current may not go fast enough. Rescuers should be prepared to have a succession of swimmers go down.
Meanwhile, sometimes a line can be put across the river and rescuers can be ferried to the victim's location. That's going to take long enough that immediate CPR will be imperative.
In my case, I probably was not entrapped for more than a minute, maybe for less than 30 seconds. Something in my trapped knee gave way and released me, to hobble around for months afterward. If my lunching companions had realized I was trapped, I was close enough to the lunch rocks that deep wading might have gotten someone to me in reasonable time.