We arrived at the Sticklinch parking lot around noon or 1 last year, and the queue at the Sticklinch entrance was around 10-15 people deep. This queue was definitely shorter/faster than the queue at PGA.
We had to pick our tickets up from the international ticket booth, so we had to walk from the Sticklinch parking lot to PGA. As far as we could tell, it wasn't possible to go the way you're planning to go, as there is a house in the way, and we didn't want to walk through someone's yard.
I drew a red line on the path we took.