I got this when I accidentally fell through the island at a certain spot, I'll upload a video, the glitch is pretty easy to replicate --- "Yin and Yang are not good and evil. Their unity is good, their struggle is evil"
100 m free fall: Simply don't open the parachute when flying in a plane from the northern to the southern island (which is story-related, so you can't miss it) 60 m dive: Basically any dark blue spot in the ocean
For the dive 60m challenge, there is one relic which is located off shore in a small spot of dark blue water. Dive down to get that and you will get the trophy. --- You will be baked, then there will be cake.
You can also use a hang glider for the free fall trophy. Just fly over the ocean, look down and release. (kind of fun, actually...lol) --- "Once upon a time in the West, there were men like this. They were not noble; they were not heroic. They simply were." PSN: Ninkyodo893