After the "Miracle Flood" when the 3 runaway fugitives are floating on the coffin, you see them staying in one place, maybe drifting right a little bit, while floating debris are rushing left. They aren't paddling against the current, and those flood waters look pretty strong. It's not really a big deal, but quite noticeable.
I disagree. If you watch the distant background, you will see they are definitely drifting with the current. Of course they are not drifting at the same speed as the debris floating on the surface. Six legs sticking down in the water are going to add some drag. Also, it will take more force to push the combined weight of three adult men than a piece of driftwood or a can of pomade.
They ARE drifting slightly, just not as fast as the other debris. The three of them might be kicking their legs against the current so as not to be swept away.
Also, you will notice that you can see the stir of water that occurs by the motion of a bout propeller in the water directly behind them. And how did there hands become untied? (they were tied before the noose was to be placed over their heads)