If you look at the previous fight, Haney prioritizes distance more and he is not in a hurry in carrying out his strategy. We can see when he attacks and is about to be countered by Kambosos he immediately keeps a safe distance and always starts from the beginning. On the other hand, Kambosos has been carried away to Haney's battle scheme which makes him unable to avoid and ultimately loses in absolute terms.
The moment Haney dictates the tempo of the fight, Kambosos already lost the match. So this coming match, Kambosos shouldn't let Haney dictates the pacing of the fight. Kambosos must come up with some strategy that will make him nullify Haney's attempt to dictate the tempo.
I could say that Kambosos needs tons of adjustment if we want to reclaim his belts. Styles make a fight and it seems to me that Haney's style is not suited for a slugger like Kambosos, the latter is a bit slow for Haney. The first fight is not even close so for me and changing one's boxing style can't happen overnight so for me this exercising of the rematch clause is just for the money, result will be the same (just my two cents).
That's his problem, he was very slow in their first meeting, Haney can predict his game plan so he cannot win if he uses the same strategy. I think he needs to conserve his energy, be a counter puncher and make the right timing, that way if he can hurt Haney, there's a win that he can win by KO.