Nidorina is available ?

[JABZYMADMAN 1]

I was going through the nuzleaf cave (Requires rock smash) and then i saw a lever, when i pulled it i saw Corey's nidorina. Although people keep on saying it's unavailable unless you cheat. if nidorina is available  without cheating. Is there and more pokemon that belong to Corey in the wild (other the nidorina and croagunk)?

[Swampellow 116]

You need Corey’s Silver Ring to obtain his Pokémon.

[Starry Knight 753]

Stuntank is also available

[Aura_Guardian 6]

Where?

[Starry Knight 753]

Same mountain as Crogunk but lower

 

There is YouTube tutorials on finding it

[FriarTruck 2]

I think Skuntank was on ground floor/1f level of celestine cascade available after reaching the circus. There's a strength rock on a bit of ice you need to move past. You might need waterfall idk.