Shemeska
Adventurer
"End of Eternity" has the party visit the Elemental Chaos replete with Primordials (renamed "proteans") - the Pathfinder issue even dedicates a whole ecology article to them.*
I'd be surprised if it uses any of the WotC terms *goes back to look at my copy*
But regarding the proteans in PF#22 (and in Paizo's planar book as well). The proteans' home plane is known as The Maelstrom. And they're conceptually very, very different from WotC's primordials. WotC's primordials are vaguely like the Greek titans, and have a thing against the gods of 4e. The proteans are more like a physical manifestation of the Maelstrom's reaction to the rest of the cosmos, like an immune reaction to the advent of a very foreign concept of law and stability.
They were there before the gods but perhaps only within Golarion's cosmos, since it's not a settled question of where the gods came from in the first place. The proteans also don't have any monolithic ideology, instead being split apart into innumerable groups -called choruses- each with a specific vision of how to carry out the Maelstrom's will. The gods also don't have any monolithic interaction with them either, excepting perhaps Asmodeus.
That said, if you use the proteans, regardless of what cosmology you set them in (heck even plugged into 4e's default) I'd be flattered. A lot of stuff I make can be adapted to other cosmologies if that's your thing, though some of the larger context they were created within might be lost if you don't also bring along some other concepts with them.