It is not possible to level all the way up in the Shaman Class. It fails eventually.
any of the feats it has, or it might even be possible to previously TAKE all the feats (from multiclassing), and have nothing left to select. At that point you are screwed and cannot take anything, and cannot level.
I guess I'd solve this by giving it some feat chain that has no prerequisites and can be taken multiple times, like the Epic Toughness chain (not that I'm suggesting that, just top of my head thinking of a chain that qualifies). That way the class has a guaranteed selection available when receiving a bonus feat.
That said, if you are very careful in your build, and ensure you hit the prerequisites for bonus feats in time to take them, then the shaman should be able to level without issues.