After WWII the British North Borneo company which had run North Borneo didn't have the financial resources to help reconstruct the country so turned it over to the British government to become the Crown Colony of North Borneo, the already existing neighbouring separate Crown Colony of Labuan was also joined with it at the same time. The western ruler of the Kingdom of Sarawak for similar reasons as well as family ones similarly decided to turn his kingdom over to the British, something which wasn't very popular with the locals, to become the Crown Colony of Sarawak in roughly the same time period. Fast-forward fifteen years or so and the two colonies join with Malaysia as the states of Sabah and Sarawak respectively.
But suppose that Sarawak had stayed an independent country rather than becoming a Crown colony. Now you've got it and Brunei sitting between North Borneo and mainland Malaysia, do people think that the locals would still decide to join with Malaysia or might it affect things to maybe consider striking out on their own? I think on balance they'd probably still join them anyway since even in our timeline they were over the South China Sea from the mainland but figured I'd see what people thought as I don't know a massive amount about the area.
But suppose that Sarawak had stayed an independent country rather than becoming a Crown colony. Now you've got it and Brunei sitting between North Borneo and mainland Malaysia, do people think that the locals would still decide to join with Malaysia or might it affect things to maybe consider striking out on their own? I think on balance they'd probably still join them anyway since even in our timeline they were over the South China Sea from the mainland but figured I'd see what people thought as I don't know a massive amount about the area.