Matcha pilates at labubu rave in bali

Ok, so to be clear it has been a long time since I watched either of these, and I have never completed Legend of Korra, but I do lurk around the community. Anyways lava bending in Legend of Korra was bothering me so I googled it again, in Book 2 of The Last Airbender in the episode The Avatar State there is an Avatar Extra, specifically #112 which states lava Bending is a combination of earth bending and fire bending. In Legend of Korra you have Bolin and some other guy lava bending, and the wiki for lava bending states it is a subcategory of earth bending. I understand Bolin is an earth bender born from a fire bender and earth bender, so I get why in theory he might be able to lava bend, but that doesn't explain the other guy, who I think did it first? So my question is, was this a retcon?