Yep and I think that is what happened here. They gave him progress to the point where it appeared the teammate's help started to have an impact. May be a better solution than yet another flag.
In this case, I think that was the best solution, and it was an easy call because there was pretty good evidence his progress had been stopped anyway.
Had he still been moving forward, this is an example of one that would be a pretty obvious call. Pushing from behind can almost always be "overlooked" because in most cases, it could be considered pushing the pile, not an individual runner. But grabbing the player by the waist and pulling him forward? Tough to overlook that one unless you decide the runner had already been stopped, in which case this becomes nothing.