Strat evolution - with enough of a delay and dropping back down to the 2nd rising pillar, it's possible to get to the 3 Octoballoon area from up there in the 10 second time span that you have. From there, it was a matter of landing the 1 Super Bomb shot necessary there, and then using IDA to get rewinded back to just after the door opens there, skipping the cutscene and maximizing movement with an FF. With that, the time here was knocked down almost 2 seconds, bringing the total time down to 12:46.16.