What if Vigilante Deku accidently killed Dictator?

Hypothetical here I've been wondering about. Despite his physical and mental exhaustion, we see that he could still put up enough of a fight to use all of his quirks against Class 1A so he clearly wasn't too exhausted to use his power.

What if hypothetically while fighting Dictator, let's just say Class 1A takes longer to come by. What if Deku accidently uses too much force attacking him(due to exhaustion) and accidently kills him? How does this change Deku?

How would he, the people watching, and Class 1A react to that?