December 8, 1968: Chicago Bears @ Los Angeles Rams

The Rams gain possession in the fourth quarter trailing 17-16. An offensive holding penalty, which at the time was a 15y penalty from the spot of the foul, was assessed after the first down play. However, the officiating crew failed to repeat first down.
The Rams didn't notice the error and ran a play on 2nd-and-31.
Could the error still be corrected?