So what if instead of the Spanish forces abandoning Brunei due to an outbreak of sickness amongs their forces, the Spanish suffer a a milder outbreak that does not weaken their forces so much. Spain conquers Brunei, winning the Castillian War and gains itself a foothold onto Borneo
How does this change Spain position in SEA?
Will it change the colonization of Philippines?
What would a Spanish Colonization of Borneo look like?