You forgot PartMan, Nyx, DaWoblefet, zoro, Theia, Breadstycks, Notater517, Mathy, UT, and Venous.

PartMan -
252+ SpA Tera Fire Scovillain Mind Melt vs. 252 HP / 0 Def Chandelure in Sun: 173-204 (53.3 - 62.9%) -- guaranteed 2HKO

Nyx -
252+ SpA Tera Fire Scovillain Mind Melt vs. 248 HP / 0 Def Altaria in Sun: 173-204 (49 - 57.7%) -- 96.1% chance to 2HKO
252+ SpA Tera Fire Scovillain Mind Melt vs. 252 HP / 0 Def Altaria-Mega: 97-115 (27.4 - 32.4%) -- guaranteed 4HKO
Lives the initial switchin, and can KO back with earthquake. This is a check, but only for as long as there are no hazards up.

DaWoblefet -
Yeah this one is pretty good, although its always gonna be a 1 for 1 trade.

zoro -
252+ SpA Tera Fire Scovillain Mind Melt vs. 252 HP / 240 Def Umbreon in Sun: 236-278 (59.8 - 70.5%) -- guaranteed 2HKO
Because of the ability this one can be a bit annoying, but its not exactly a super safe switchin either.

Theia -
252+ SpA Tera Fire Scovillain Mind Melt vs. 0 HP / 0 Def Eviolite Power Abuse Litwick: 113-134 (14.355 - 17.16%)
Ok, this is actually really solid. Shadow ball is also almost always a 2HKO on scov, so this one is actually a good counter.

Breadstycks -
252+ SpA Scovillain Solar Beam vs. 252 HP / 4 SpD Dachsbun: 228-268 (71.6 - 84.2%) -- guaranteed 2HKO after Leftovers recovery

Notater517 -
252+ SpA Tera Fire Scovillain Mind Melt vs. 252 HP / 0 Def Incineroar: 115-136 (29.1 - 34.5%) -- 5.6% chance to 3HKO
Not a lot of damage, but Notater517 doesn't get recovery, so it's just a matter of chipping it everytime it switches in until on the third switchin, it gets 3hkoed. However because it has ceaseless edge, it can at least guarantee chip on further switchins.

Mathy -
252+ SpA Scovillain Solar Beam (??? type) vs. 0 HP / 0 SpD Furret: 160-189 (45.5 - 53.8%) -- 44.9% chance to 2HKO
252 Atk Furret Bitter Blade vs. 0 HP / 0 Def Scovillain: 113-134 (41.6 - 49.4%) -- guaranteed 3HKO
Not necessarily a clean 2HKO, but doesnt deal enough damage to avoid growth into kill.

UT -
252+ SpA Tera Fire Scovillain Mind Melt vs. 252 HP / 4 Def Fur Coat Talonflame: 70-83 (19.4 - 23%) -- possible 5HKO
Ok this one is actually a genuine very solid switchin, don't know how I missed that lol.

Venous -
252+ SpA Tera Fire Scovillain Mind Melt vs. 248 HP / 244 Def Mantine in Sun: 158-186 (42.3 - 49.8%) -- guaranteed 3HKO
Yea, not good enough, not to mention growth is free against this.
So adding Theia and UT as real counters and DaWoblefet and Nyx as solid checks, that's still only 10 mons in the tier with real reliable ways to deal with Solaros & Lunaris.