It’s almost silly to think the Spaniards at least stumble across the Hawaiian Islands. A Manila galleon would pick up a mid latitude westerly and keep going until it hit the North American coast, perhaps as far north as Oregon; as big and spread out as Hawaii is, well... A sailor doesn’t even need to be within site of the islands, the cloud formations that form above them would be instantly recognized by the greenest hand and can be seen for well over a hundred miles. And surely the Spaniards encountered more than a handful of Polynesian seamen who would have at least been aware of Hawaii. Finally, the fact that map information is ambiguous; a right thinking treasure ship captain would carry two sets of charts - one for navigating, and one to be captured with.
That’s “didn’t at least stumble”, and “sight”. Dumbass.