[AmityvilleHams]

I've never had any issues with my dog and Whimzees, nor have I ever heard of them making a dog throw up. I have heard that about Greenies though which are a very different chew - one I personally wouldn't recommend at all for any species including dogs and hamsters. Of course some dogs might still be allergic to Whimzees despite them having very limited ingredients which aren't really that common for dogs to be allergic to.

In terms of the rattan wobble ball and eating the second inner ball I would keep those for out of cage use if a hamster is actually getting inside the first ball and eating the second one mostly because there's a potential injury risk if a foot were to get stuck in a hole. Alternatively you could try hanging it up where it can be somewhat chewed(you'd probably have to occasionally rotate it manually to keep it chewable I'd imagine) but not climbed into. I can't say for sure it's all that safe to eat so much water hyacinth either so definitely make sure your hamster is eating enough actual food for dietary balance and such!