To try to guess what is going to happen on Banni's route we have to see the information we have from this update:
1.-Banni is loyal to Dion (The Bovo general) mostly because he provides the pirates with means for a good life
2.-Izashi is the only one who can fully control Banni's crew, not even Banni himself can do that.
3.-Dion hates pirates but needs them to maintain his "peace", specifically he mentions that only Banni and Izashi are somewhat useful, the rest are disposable
4.-Taavi also mentions that Dion will replace all the pirates with more of his men.
5.-Zhokhar mentions that he heard from Banni's crew that Banni himself has suffered physical abuse at the hands of the Covenant (scars and holes in his fins, which have only increased much more since the last time he saw him on Aris).
Using this information we can start to form a theory but what will happen on Banni's route will also be influenced by how Dion acts after the disaster that Killigan's group left behind when they escaped:
1.-Dion will imprison Banni's crew for mutinying against the Covenant. If this happens it is likely that he will replace Banni's entire crew with bovos and send him to hunt Killigan across the entire coast. Banni will most likely let this happen because he didn't protest when Dion suggested it earlier, plus he's very focused on getting revenge on Killigan.
2.-Dion will execute Banni's crew (or at least try to), this will cause Banni to directly confront Dion and the entire Covenant. If this happens, it is likely that at one point in their confrontation Dion will reveal his true intentions towards the pirates (proved by the fact that he was already looking for Izashi's weak point) which will immediately antagonize him with the Covenant and make him a fugitive. Without a crew or ship and totally alone, the only thing that will move him will be to go after Killigan.
3.-Dion will give Banni and his entire crew an ultimatum and send them to hunt Killigan, in this scenario Banni keeps his crew but it will be for a very short time. Based on what Taavi said, Banni's entire crew is already tired of following the Covenant orders so they will mutiny again and may abandon Banni, leaving him with absolutely nothing.
No matter which of these scenarios occurs, what is certain is that Banni will not stop hunting Killigan and will be following him relentlessly, whether by sea or by land, just like a shark hunting its prey. So how on earth will Banni go from swearing revenge to swearing eternal love towards Killigan? The only way is for Banni to see the truth with his own eyes.
During Taavi's execution, Banni was already having doubts about Dion's words and actions but was more concerned with preserving his lifestyle. It will be during his trip hunting Killigan that he will have many opportunities to see the truth, he will be remembering the last words of Izashi, encountering daemos and realizing that they are not much of a threat (considering that even the clutchmates were able to defeat some on their trip) in addition to that he will be able to experience firsthand the effects of the Dreadstones on all of Canavar. The point is that when he finally catches up with Killigan he will be so full of confusion and heartbreak that he won't know what to do anymore.
There is also the possibility that even seeing everything that happens in Canavar he will not be able to let go of his fury when he reaches Killigan, which will cause him to face the entire group and lose. At this point it is more likely that Taavi can reason with him, since she is Izashi's granddaughter.
In any case Killigan will be able to empathize with him, since they both lost loved ones. This will be the basis of the relationship, where Killigan will support Banni throughout the grieving process. What happens next I am no longer sure, everything will depend on the place where these events occur. But what do you think of this theory?