Well, Cinderhulk really is just better than the other jungle items right now. I mean, you build it over the other items on anybody who can plausibly use it.
So, the smart thing to do would be reasonable Cinderhulk nerf and then small buffs to non Sejuani tier tank junglers.
But the problem is that tank junglers are really hard to balance because they are typically fairly strong in low ELO but weak in higher ELO. I mean, Amumu would probably need a compensation buff in high ELO, but is super OP in low ELO because they don't know how to handle him there. So it is really tricky.
So Riot will probably make a mess of it given how they usually handle jungle. Double nerfs where you nerf a jungler and their favorite item like we see on Sejuani are how champions get essentially deleted from the game (see Warwick).