I saw it happen in 2003 in a Conference game between Doncaster Rovers and the old Telford United. A Telford player hit a shot from distance into the top corner and the ball went in and bounced straight out. The referee, Steve Brand, didn't see it go in and let play continue. So while Telford's players celebrated Rovers carried on and almost scored up the other end!
The goal wasn't given but justice was done as Telford won 3-1. In the recent instance I can't really understand how all the officials have missed the fact the ball was clearly over the line.