Henry is trying to help Dorothy by removing the Desert Thorn that's stuck in her, but a crack now prevents access to her.

I'm not sure this puzzle flows logically, I solved it by accident, so I'm not sure how to explain it.

But, firstly, notice if anything has changed nearby.

A Flag has blown down and can be found nearby.

There are a few little clues close by. Notice something about Wrangler and something about the Ceramic Pot.

Wrangler is sneezing. And Henry wants to flush the creature out of the Ceramic Pot.

Maybe Wrangler wants a Hanky.

You already have it. (It's the Flag.)

Perhaps you could scare, or disgust, the critter out of the Ceramic Pot?

Use the Snotty Flag on the Ceramic Pot.

Again, I'm not sure how to hint at this because it doesn't make logical sense to me until after the puzzle is solved. Retrospectively, I could say this ... Perhaps Dorothy is thirsty.

Use the Ceramic Pot on the Murky Water, to the left of Wrangler. Use the Filled Pot on the Crack. Dorothy will come to drink, so you don't need to cross it after all.

You can now remove the Desert Thorn from Dorothy.