To be fair, it doesn't look to me like they pushed him into the bush, they were all jogging, they grabbed him when he got to close and quickly took him to the side to get out of the way of the procession, the momentum of that, and the fact they were holding on to him meant that they ended up in the bush.
I've watched it another couple of times and I think I see what you mean. However he's trying to get back up from the bush and one of them is keeping him in it. Perhaps it was an accident, however shoving someone who is running will likely result in them falling over, and there was no need for a shove.
It's not a big deal really... the police were probably not needed other than that one point, which is possibly why they were a bit over the top.



