Revelations from Patch 6.3: Gods Revel, Lands Tremble

[Mieck]

I work under the assumption that only Etheirys (and I guess the moon too) was sundered, but yeah, last time Square was asked this they said they aren't sure if it was just the planet or the whole universe either.

I think we've had a soft confirmed answer in 6.0, though.

Vrtra confirms both that his father arrived on Etheirys post-Sundering, and that he only saw one world - the Source.

But on the wider point that I don't think Yoshi has ever directly addressed the above point out of game, yeah, I think SE's last statement was the ambiguity you suggested.