I’m wondering if there may be something wrong with his teeth, like a spur or something, that’s making your bunny not want to chew. Is he eating alright?
Other than that, Meki’s a picky chewer. I’ll give her wood blocks and willow balls and wooden carrots and none of them are interesting. On the other hand, she loves to chew the support beams in her cage at night (literally the same as a wood block, but the wood blocks aren’t apart of her cage so they’re not interesting/fun).
What I find that she DOES consistently chew on, though, are thin little untreated apple tree branches. There were a few apple trees on a curb strip by my house that I knew 100% were not treated with any chemicals and sometimes the tree would sprout some smaller, softer twigs where an old branch fell off. I’d snip a few at a time and give them to Meki and my old bun Nefi and both of them LOVE to chew the bark off. Maybe it’s sweeter and tastes faintly like apples? not sure, but if sticks keep them happy, why not.
Meki also likes big woody pinecones that have opened, too, but I always feel safer buying mine from a pet shop just because pinecones travel and I’m not sure if the tree had been treated or not.