By item sliding against a lamp for long enough, it is possible to get the camera to sink. This is called a Weirdshot. First, item slide against the lamp while holding the hookshot button. When the camera starts to sink, be ready to release the hookshot when it reaches sea level. Then, L-slide around the walls and up the stairs to get in front of the door and hookshot the tree. The game will take Link's actual position (on the ground) and pull it to the tree, effectively making him go through the loading zone.
If your hookshot hits the invisible collision of the Cabana before the tree, it means that you stopped your weirdshot too high. If you're too low, you can gain height by tapping down or ess down on the control stick.
Note: Pressing ZL while Link is not using the hookshot will cancel the weirdshot.
By using an L-Slide clip or buckets to clip into the stairs under the Cabana, you are able to get to a position where you can hookshot the mailbox from across the Cabana. Using a frame perfect bomb boost from a L-Slide clip allows you to skip the Cabana Deed.
This can also be done with multiple frame perfect tricks.
First, item slide forward with iron boots on in front of the door. Once you have enough speed, hold up on the control stick to make Link's speed go from negative to positive and then quickly release the hookshot button. It is possible to hookshot the tree through the Cabana, which will pull Link to the tree and go through the loading zone. The reason this works is because item sliding forward with iron boots while holding up on the control stick makes the camera shake and quickly sink into the ground, allowing for a weirdshot.
Alternatively, using the same trick, it is also possible to hookshot the mailbox through the wall to skip the Cabana Deed
By doing an perfectly precise island hop, it is possible to make it inside the Cabana before the collision has even time to load, and hit the loading zone.