I think you may have the FR elementals mixed up with Moorcock's.
What I see in my D&Demigods is: Grome, lord of earth, Kakatal, the fire lord, Misha, lord of wind, and Straasha, lord of water.
Nope, that exactly how FR's elemental lords started out.
Dragon 54 Down to Eath Divinities by Ed Greenwood lays out his construction of the FR pantheons.
DR 54 Page 54:
"THE ELEMENTAL LORDS
Moorcock’s Elemental gods from DDG (Grome, Kakatal, Misha, and Straasha) may later be replaced in my universe by “official” AD&D beings as these are published; hence, they are usually referred to by their nicknames. Although in play I have tried to keep their powers hazy, their characteristics are taken straight from DDG."
Kossuth and such did not show up until
1e Manual of the Planes and then were incorporated into FR instead of the straight Moorcock elemental lords.
1e MoP Page 40:
"Archomentals: Of the various elemental princes and other petty potentates of the plane of Fire, only Imix has been described. There are others of various alignments, intentions, and beliefs, but they have abilities similar to Imix's. The archomentals are considered Demi-Powers in their own planes.
Imix is said to make his fortress in the heart of a great active volcano, ringed with volcanic rocks and protected by frozen eruptions and explosion fields. Imix seeks out such pockets of unburnable basalt and other volcanic rock to add to the defense of his home. He is extremely paranoid about cold, ice, and especially water in his domain. His great cohort of a dozen fire elementals of maximum stats patrol his borders constantly, seeking any who dare to disturb the slumber of their lord. Those who seek out Imix are warned that there are easier ways to achieve destruction.
Kossuth: The tyrant-king of all elementals is known by many names, all of which sound like the rush of super-heated air from a foundry or the crackle of lesser matter being immolated. Kossuth dwells in a palace built of elemental fire in a hot spot at the center of the plane. The heat here is so intense that even creatures totally immune to flame, such as fire elementals, take 1d2 points of damage per turn unless protected by Kossuth.
Kossuth is quick to judge, and his judgments always revolve about what is best for his dominion in general and himself in particular. He expects absolute honor and loyalty from all who serve him, and has been known to overwhelm those who displease him, elemental and prime traveler alike, with the power of his flames. Kossuth is a Greater Power, the primal power behind all flame, and as such is unslayable in his home plane and has all the abilities afforded a Greater Power in Appendix IV (page 124)."
The good archomentals I believe were not mentioned by name until 2e.
Also of note 1e MOP page 25:
"The most powerful elemental creatures, called the archomentals, are great beasts that are individually named and may stand toe-to-toe with the lesser deity-class creatures of the outer planes. The rulers of the various elemental types are called "elemental princes." The evil elemental princes have been described in the FIEND FOLIO® tome"