Has a College Football game ever ended 28-4?
It has. 28-4 has been a College Football final 4 times in 84,433 games. The first was Harvard beat Stevens on October 5, 1889; the latest was Syracuse beat Michigan on November 21, 1908.
That makes 28-4 the 1362nd most common final score out of 2,216 that have ever occurred in College Football. One point away, 29-4 has happened 3 times and 28-5 has happened 13 times. Nearly all of its occurrences fall between 1890 and 1919.