[Dug89]

What about hammering on a slightly smaller 12 point imperical socket (not metric). I don't know what the next size down US socket is from a 19MM but it might be worth a try.

Make sure the other 4 nuts are on at normal torque to relieve stress on existing lug nut.

These lug nuts are aluminum so they don't handle stress well from the stock lug wrench or impact tools. Best to use a 1/2 breaker bar and the plastic lined sockets.