Rules Analysis
If the disc initially contacts the playing field and then becomes out-of-bounds without contacting an offensive player, the thrower must establish a pivot point where the disc first crossed the perimeter line, or the nearest location in the central zone if that pivot point would be in their defending end zone.
If the disc does contact an offensive player before it becomes out-of-bounds the thrower must establish a pivot point where the disc first crossed the perimeter line, even if that pivot point is in their defending end zone.