I was with you up to here,But this is going too far.
Ok - I guess I would be ok if the homeowner, while protecting his life, his wife's life and his home had left Vincent with a disability that prevented him form re-offending, rather than killing him.
For me it depends on the victim - in Vincent's case, given he was armed with a screwdriver and was not stealing out of need, I think it's a good thing Vincent is not walking around looking for his next victim. If he went to court he would have been out of prison fairly quickly and free to threaten people with screwdrivers - he could have ended up stabbing the homeowner or giving him a heart attack, or pushed him so he fell and hit his head and died.
So in that sense it's a good outcome that Vincent is not around to cause those kinds of problems. And it would have been hard for the homeowner to have gone through the trauma of stabbing Vincent, so I feel sorry for the homeowner to have to deal with an attempted burglary and then have to stab someone.