If you mean deliberately cheating and getting away with it with little to no penalty? Sure, it just happened to Patrick Reed at the Hero World Challenge and has happened to others in the past.
Has someone deliberately cheated and gone on to win a major championship? I'm not sure. My knowledge of golf history is quite limited compared to others on here.
8 minute window es a LOT !!! you also took 5 mins to finish 8th hole so this group ahead of you took 13 minutes to have a snack!! at my home course that´s at least penalty or DQ. You are only allowed to stop 5 minutes if your pace with the group ahead is good, if not you cannot stop.
In this case i would let the other group know and tee off ahead of them, reinforcing the fact that they where 1 or more holes behind the next group.
I'm hoping to play both days. In chicago for work now and its hard to believe that it will be playable on the weekend back in dayton. Fingers crossed for rounds 6 and 7 of the year. Maybe 8 if I'm really pushing it