We can't know how hard he hit him for sure but it looks like a little pat, the kind you might give someone you were supporting. Without being there and seeing how hard the tap was it is impossible to be certain but it looks like G is using this to pretend something happened to him which did not. I have been in a crowed street and felt something like that. He seems to be using his age to try and get at the man. It is not to do with age. It is to do with health. If a tap on the back makes him feel his life is in danger then clearly he is not well enough to be doing this work. He has to take responsibility for himself too.