This happened to me during casual play and I just spent about an hour trying to recreate it. I finally got it, although the video quality is poor.

As you can see, it (presumably) won't let you progress to Mushroom Rock Road.

I'm not sure if this is known or even helpful but I wanted to post it just in case!

Wow that's pretty interesting. If there's a way to trigger the loading point for MRR you can save a few minutes there.

If you could force yourself into the zone, it's a 2 minute save.

What version of the game were you on?

I went back and looked it up. He was running the PS3 version. Once I have spare time maybe I can try to recreate it.

Right, it was the PS3 remaster I was playing.

I've since recreated it and tried to move Tidus beyond the zone but the game wouldn't let it happen. But I think it could use more testing.