Short answers, pulled from the story.
Admiral Mineichi Koga died when his Kawanishi H8K aircraft crashed into a typhoon. His chief of staff, Vice Admiral Shigeru Fukudome, also crashed in an accompanying plane but survived.
Filipino guerillas recovered documents from a crashed Japanese aircraft and transported them to General Douglas MacArthur's Military Intelligence Service in Brisbane. The service forwarded the translated plan to Admiral Chester Nimitz in Honolulu by June 1944.
The submarine USS Albacore sank the Taihō with a single torpedo strike that ruptured aviation fuel tanks. The submarine USS Cavalla sank the Shōkaku after hitting it with three torpedoes which caused a catastrophic explosion.
Japan lacked oil tankers to transport petroleum from the Dutch East Indies so their carriers used unrefined Tarakan petroleum that damaged boiler tubes. This fuel created explosive atmospheres incompatible with damage control procedures while Japanese pilots remained inadequately trained compared to U.S. aviators.
Japanese losses totaled three carriers, more than 350 carrier aircraft, and around 200 land-based aircraft. The United States lost only three carriers across five major carrier-on-carrier battles including this engagement.