Antoni notices the torches when they're still a few blocks away.

He could almost certainly take any individual member of the crowd. He could probably take several of them at once; he has years of battle-hardiness on his side. He is not at all confident that he can take the entire mob at once.

Antoni is not easy to kill, but the first step in not being easy to kill is not letting himself be trapped somewhere with no way out, at the mercy of people with no reason to care about him. You know, hypothetically.

If they manage to pen him in in the mansion, it'll be too late to do anything but fight and hope he gets lucky. It's not that he wants the mob to destroy his property, but lost wealth can be recovered; a lost life won't be, not when there are so many people who stand to gain from his death. It's not like that much of his material wealth is both present in Westcrown and not on his person.

He orders a few of his servants to pack up his most valuable belongings that he isn't personally carrying and sets off with his guards.

(He gets lucky. He doesn't encounter any splinter-groups of rioters, and when the rain drives him back to his lodgings, they haven't been ransacked. He doesn't even have to kill anyone.)