"Ah... Let me see this bottle for a moment. Set it on the beach? I don't have grand, impressive magic, but little things can make all the difference sometimes..."

She puts it down in front of the boat.

He chants in some strange language. Little motes of light appear and the world goes dim for a moment.

Then it's over. The bottle doesn't look different, exactly... But it's clearly not just a regular glass bottle anymore. "That should make any liquid it holds better. Water more nourishing, soup more filling. I don't think I can do that often."

"Cool! I'll take good care of it then."

"Hopefully your exploding venture goes well." Is that sarcasm? ...Probably not.

"Yep!"

Back to the cavern.

The wind is still chaotic. The bomb plants are still withered.

Bomb plants, meet hopefully super effective water!

The two that are sufficiently splashed swell up to full size over about a minute.

Neato.

Then bomb plant can meet boulder. And fight to the death!

Spoiler: Boulder loses.

The spring starts blurbling up through the pebbles immediately. It's kind of slow though... It'll be a while before this pool fills up enough that she can swim to that ledge. She can still get out of the end towards the village just fine, of course.

All right. Not much she can do about that. Back to the village for now, then.

The village is still curiously deserted-ish.

The spring wasn't that slow. It'll probably take about half an hour.

She can sort mail for half an hour. Make a couple rupees while she waits.

Eight.

The pool is deep enough to swim across when she's back, and even looks reasonably fresh despite the ash in the air. She might want to refill her bottle.

Yep, she can do that, then it's time to cross. Finally.

Her first obstacle is a pit of lava maybe twenty feet long with two big statues holding large jars along the walls. They'd make a good bridge, if they fell. There are bombfruits nearby.

Explosive fruit: surprisingly useful.

So if she plants them at the base of the statues that should work, right?

The statues are over the lava. She can't actually reach the base of them. Could throw a bombplant there easily enough.

She can throw them then.

This creates a bridge of destroyed statues over the lava.

Which she can then cross safely.

The next room has a big elaborate door that seems to be blocked by slightly less giant statues which are, at least, upright. No bombfruit near enough to ferry them here safely.

...Is there maybe a less elaborate hidden door somewhere?

If there is, it's pretty well hidden. The statues are small enough to be possibly pushable.