
Often stud dog handlers will hold a dog in place to ensure a tie, most often in breeds where the males are smaller than the bitches and tend to slip.
They will hold them for at least 5 minutes so that even if they don't tie there will have been long enough contact for the goods to be delivered.
Where they back to back during the holding or dog atop the bitch. If the former I would say there was a successful tie (as otherwise they would have parted during turning).
I'd certainly still expect more than one mating opportunity.