I don’t think anyone disputes that Spanish explorers reached what is now Oregon before English or French ones did. The question is where did the name come from.
The best evidence is that the English acquired the name from a distance, without ever visiting the place. In 1765 Robert Rogers, a British military officer, heard from some of the Mohegan people of Connecticut about a great river that flowed to the Pacific (assumed to be what is now called the Columbia River). The Mohegans called the river wauregan (beautiful). There are also French accounts of a similar river dubbed la Belle Rivière. This path is quite well documented, and it is certain that the English name comes via this route.
Another possibility is that it is from the Shoshone oyer-un-gon (place of plenty) or ogwa pe-on (river of the west), which was subsequently reanalyzed by Algonquin speakers in the east to mean “beautiful,” and thence into the English and French.
If you actually have earlier evidence of the Spanish calling the place or the river Oregon or Orejones or anything similar, we’d love to see it. It might show a Spanish origin, or strengthen the idea that word comes from Shoshone, with whom the Spanish would have had direct contact.
It is kind of odd that the entrance to San Francisco Bay went undiscovered for so long. However, the telescope hadn’t been invented, and maybe the ships didn’t hug the coast. As a side note, I have a hard time believing Drake beached the ship at Point Reyes for a month of repairs but didn’t get out and about enough to discover one of the largest and most ideal bays in the world. But there’s no record of it.
Point Reyes is a fair distance, at least by sixteenth-century standards (about 30 miles), from the opening to the San Francisco Bay. I have no trouble believing that if he did in fact land at Point Reyes (which is by no means certain), that he wouldn’t have ventured on foot or by small boat as far as the Bay. Also, given the marine layer fog that hangs over the San Francisco Bay for much of the year, it’s perfectly plausible that he might have sailed by it several times without ever noticing it. He was in the area in June 1579, and June is month known for its fog over the Bay.