Considering the fact that Gank Isle is surrounded by acid water that deals a significant chunk of damage, it was very clearly not intended for people to go out to the FAR BIG SEAS and dig down into the water. If you want to use hole strategies, you should do it on the land or on the cliffs. Water strategies on Gank Isle are something that very obviously were not intended and have been heavily abused.
Gank Isle is built for teams fighting and multiple players taking on other players, it's very clearly supposed to be chaotic with "no rules" in a sense. If you are split off from your team, or don't have one, you shouldn't expect to win if there is a team out there. Scumming is allowed these types of areas Gank Isle isn't for some generational 1v5 plays. People can do what they want, but you are obviously not supposed to leave the island and hide in the surrounding ocean It's a really obvious thing considering, again, it’s surrounded by water.