Ever since he felt abandoned by Velen, Chieftain Hatuun has borne a grudge against the Draenei who was once his friend. Now, finally, and in part thanks to the Draenei Heritage questline, it seems the two are ready to reconcile.
The Draenei Heritage armor questline centers around Tishamaat, a yearly sacrament once celebrated on Argus, during which Draenei reflect on the burdens of their past, learn from them, and commit to a path forward. In the lead up to the event, we learn that Velen has asked Chieftain Hatuun to help him with a demonic threat in Bloodmyst Isle. Hatuun is no fan of Velen's, and does not plan to attend the Tishamaat, but he comes to help — partly because he finds it satisfying when Velen admits he cannot solve a problem by himself.
Once the threat is dealt with, Velen presses Hatuun to attend the Tishamaat once again, adding that he's hoping to be able to speak with him there. This time, though still hesitant at first, Hatuun agrees.
At the Tishamaat, we are tasked with gathering Memory Stones from the draenei. These stones are inscribed with painful memories that the draenei wish to move on from, before being symbolically destroyed in the Flame of Reprieve. When we go to collect Velen and Hatuun's stones, we have the opportunity to stay awhile and listen to his conversation with Velen — during which Velen finally seems to convince him to consider reconciling.