I point this seems to be a real attempt to be charged.
First they hunted on as the lion was aware of their presence.
They don't shoot the lion at the right moment, they don't finish it after the first shot (back scratching).
Note the cameraman is far on the left to suck up the footage when lion is charging. He moved on purpose.
I agree, a peace of luck nobody was shot save the poor lion. A gentle lion, it acted like a leopard, striking and backing away.
A forced charge only, just to get a nice video sequence.