I took it to be the planet, before Zodiark did his thing. With the exception of the large, bright spot, it doesn't look too different from the devastated world we saw during the third leg of the Amaurot dungeon.
It COULD be Dalamud, I suppose, but that'd be pretty out-of-left-field, narratively.
Honestly, I'd brace myself for disappointment, if I were you. The storyline seriously feels as though it's building Zenos up to be the end boss, likely after a merge with Zodiark. Even if we don't kill off Elidibus first, I'll be highly surprised if Zenos doesn't turn out to be the big bad. I don't say this because I WANT Zenos to be the head honcho, mind. It's just how I feel the story is shaping.
