I have no idea where this gentleman is or what he’s shooting at.
So I don’t know why his balance is off or his footing is bad, but as a general rule, unless its life or death, you are better off not taking the shot, and getting better footing.
Most people instinctively clutch at something when they are falling, and if that was not a single action rifle, everyone, including the shooter, are at risk of an other round being squeezed off.