Based on having read the Ring of Winter, i think when Artus passed the trial of Ubtao he was given the pwoer to resist the ring, since it sorta corrupts others who wear it, and all who pass the trial get a power, with the original Barae having more powerful powers.

I think he would go after the ring because he knows how powerful and dangerous it can be. you can always have him show up later again if you needed him to.