Has an MLB game ever ended 19-7?
Yes. MLB has seen a final score of 19-7 25 times. It first happened on October 9, 1884, when Chicago White Stockings beat Philadelphia Quakers, and most recently on July 16, 2012, when Minnesota Twins beat Baltimore Orioles.
That makes 19-7 the 166th most common final score out of 330 that have ever occurred in MLB. One point away, 20-7 has happened 16 times and 19-8 has happened 26 times.