I mean, I can obviously see the resemblance, and I'm pretty sure that when more info is leaked these new Mixels will be linked to the Infernites, but I don't get why (almost) everyone on this wiki is taking the whole "they might be new Infernites" as a fact.
Didn't someone refer to them as the Vulcanites at some point? Also, look at their color scheme. They're red with very few mahogany details (as opposed to the Infernites, who have their fair share of mahogany parts), and their fire parts are transparent red or yellow as opposed to transparent orange.
Besides, wouldn't having more than 3 memebers in a tribe mess up the concept of Maxing completly? Could you Max 6 Mixels at a time (that sounds very cool but still)?