He shot the perp once outside the van, the perp then entered. At that point the van was open and both individuals appeared in the sight picture. The fact that he shot both twice from the same string of shots, proves that both individuals were contained in the target cross section. The distance was sufficiently large that Mr Beck did not have a sure shot at the perp w/o including the woman.
You made the argument well before, your last post is getting tedious with assumptions about what he saw. I am saying it ~is~ a tougher call than you make it out to be.