The weak point is not the door but the wooden jamb. It is just a two by four with a 1/2 strip of wood nailed to it.
The thing to do is get a thin piece of angle iron and drill and screw it to the jamb to spread the force of the bolt over a much wider area. You can do the same with a 1/8 inch thick plate of sheet metal that is 3 inche wide and 2 foot long. Drill a large hole in the center for the bolt and for the striker to go through and a dozen small holes for drywall screws. Then screw it to the door frame with 3 inch drywall screws.
If you want it to look normal, just put the plate under the 1/2 door frame trim board.
If she had had that modification done with a metal door, all the guy would have done is broken his foot.
ping