He resigned and has apologized publicly. Apparently he had to deal with two suicide calls earlier in the day, including one where the person shot themselves.
He was probably told he could resign and keep his benefits or be fired. It’s what happens in employment when you lose your composure.
Probably so, wanted to keep the benefits.
One thing I don't like is all the swearing the cop did at those young teens. Cops have potty mouths, something they should try to be more civil about. You can yell instructions at someone without being disgusting, particularly at kids.