Islamic way is to bury in the ground.
Only time burial at sea is permissible is if you DIED AT SEA and your vessel cannot be brought to shore before sunset. Otherwise, burial at sea is prohibited.
OBL didn't die at sea. He died on land (according to the narrative). So how does burial at sea become a funerary rite for a person who died on land, 1,200km away from sea? It's nonsense.
First you have to provide evidence that OBL & family were at THAT compound, of which you have none. And if you try to look for this evidence, you will always return empty-handed. The hard evidence for these claims simply does not exist. Only the claims exist.