Why do you create a quad of boundaries? This took me a minute to hatch using a single rectangle around the car.
I did this, because I noticed that sometimes,
the "bhatch" command works better if the area to be filled
is divided into several parts.
(. . . maybe because it is more easy to calculate the boundary . . .)
If you have a perfect shape, there is no problem.
While, if there are points where the lines, the polylines, the arcs, the splines . . . of the contour
do not touch each other, perfectly,
then the pattern enters the shape . . .