Well, you can really do this either way. It is really odd that he still won’t let you pet him after six months, how disappointing :/ Can you explain the situations that you two are in when you’re trying to pet him? For example, my New Zealand is very eager to be pet when he’s in his pen. He’ll come right up to me. But weirdly, he won’t really when I let him out to roam my room. Usually I sit on my bed and read or something, but sometimes I’ll sit down on the floor and try to coax him. He’ll come up and sniff me, sure, and will maybe let me give him a pat on the head or two, but he doesn’t care for any actual petting in that situation. And like yours, he’ll just grab a treat and run when I offer it. I have no idea why, but that’s how he is. Mu Dutch rabbit is the same way. He only lets me pet him in certain situations. So here’s what I would do: Pet your bun when he’s in his cage or pen. It needs to be a smaller space, because you want to show him that being pet is a pleasurable, safe thing. I know you’re supposed to give them space to run, but he clearly is having problems with giving you a chance. I mean, how else are you supposed to prove that you mean him no harm?
Also, you could get a bunny to bond him with and focus on making that bunny like you. If your shy bunny sees that the new bunny is letting you pet him (and enjoying the attention), he could come out of his shell more. Some bunnies are very picky about when they want attention, so perhaps you’ve just been trying at the wrong time. So try the first idea and see how that goes. Good luck!