Just some ideas on the finish of TAR20. Access to the Kaneohe Bay/Kailua Bay area of eastern
Oahu from Honolulu area is pretty easy via the
1st) Pali Highway
2nd) Likilike Highway
3rd) the H3 Interstate Highway
If they only have the tower climb and rappel in downtown Honolulu, then the Pali Highway is easiest/quickest way to get to the other side of the mountains.
On the Finish Line Stage (marked with a red map pin), upstage is to the east (right) and downstage is to the west (left). Teams always approach the downstage side of the Finish Line Stage/Mat. At the western end of the beach is a pretty open area that Production could use to have the final RB task. This possible RB area is marked with a red R.
It appears to me that teams arrive in this area via jet skis. It depends on just how far Production wants them to ride the jet skis. A good, secure launch point would be on the Marine Corps Base Hawaii, similar to the air force base in Guam in TAR11. They would have no security problems there. The jet ski distance seems a little far, but then it could explain why a team got mistaken about the location of the RB and Finish Line Mat.
A closer launch point for the jet skis could be Waiahole Beach Park, where Production could also control access if they rent it for the day. Possible jet ski launch points are marked with a red J.