Rocky Pet passive ability

[Angrytyrant]

So I was looking at rockys stats and noticed that Rockys L15 passive ability includes 50% stun chance. Can anyone confirm if this works on big bosses like the ones in glintstone/Underhul? If this is the case, Rocky with arcane ability swapped with georges stun aa would make a decent low cost stunner no?

[Ninthplague]

They say Kelvin's AA stun is better than George's