Hate and KitingFollow

Hello summoners,
Copying a post I made in the rdm forums. I am not a smn myself and know precious little about smn game mechanics, but I think I've seen it mentioned in some posts here that there are people with complete knowledge of this sort of thing, so if you can shed any light on this or point me in the direction of a post that helps that would be much appreciated.
Last night was the first time I kited anything real, and I have a few questions about hate that I figured people in this forum could answer. Me and a smn friend duod Kotan-kor Kamuy, although really it was me 98% soloing and him 98% eating delicious grauberg dirt. The basic plan: we kited to witchfire, then i ran a circle around the lake, crossed the river, Kotan went yellow in the river, I reapplied a buff and nuked or re-biod, ran a loop on that side, crossed again, repeat ad nauseum. This worked fine, so we figured he could BP, run across the river, let avatar die, lose hate when it chased him. That failed hard the first time, so I figured the game mechanics wouldn't let him lose hate until Kotan caught up to him after avatar death. Next time, he BPd, let avatar die, then ran across the river. Kotan still didn't stop in the river. My friend thought it might be a distance thing, since I was using crimson, but there were plenty of times when i was ~8yards or whatever ahead of him (ie within melee range) and he still went yellow in the river. Well, we decided maybe smn are just wonky clowns, but at 35% a blm friend joined us to speed it up and same thing - no matter how far he was when crossing the river, Kotan wouldn't go yellow. In conclusion, I have no idea wtf was going on, as it went yellow on me every single time. Any info would be appreciated, as we'd like to find a way for the smn to not be useless when we try again (0/1 on the drop).

Good call on deodorize, didn't even think to have him cast it.
Regarding the scent trail, that doesn't seem to be the mechanic here. The reason I say that is, I could be 30 yards from Kotan, and he would still beeline for me until he hit the water, so it's not that I am outrunning the trail, just that once he hits the water he loses it. The same thing would happen if he was right on my tail when I crossed the river. I'll try it tomorrow with a normal hippo when the smn logs on though to be sure. Thanks for the info.

Oh, that is a good point. With me kiting a circle, it had always been quite a while between performing any action and crossing the river. Thanks for the idea, I'll test with normal hippos later. I definitely was able to lose hate crossing the river 100% of the time, even got to the point where I would cross, get just a few feet over and automatically start casting because I knew I was safe.