When can u make Chukka join u?

Exactly when, is it after Wheel Clan or later?

 

when you go off to the isle of despair, if bates sees you have high enough persuasion and other unknown by me circumstances he tells you you migh want to try persuading him to join

 

ok, thanks

 

There's also in the dialog, if you respond hesitant at first, he'll tell you that maybe chukka will go wih you...

 

I had low persuasion (ring of influence bonus) and charisma 12 and Chukka joined.

 

where did you get the ring???

 

Is Chukka bettre than Sogg?( Both on same lvl)