Oh, I'm so sorry. I'd be devastated if I was in a similar situation.
A really good friend of mine has 4 bunnies and is incredibly allergic to grass hays of any type. And all of her rabbits are house rabbits. She has them in a separate room of her home and also has an air purifier in the room with them. When she gets hay for the bunnies, she doesn't bring it into the house until she's ready to feed it. And when she first gets they hay in she goes out with it and a mask (the kind used by doctors, nurses, and immuno-supressed people that goes over the nose and mouth - you can also buy the kind sold at home improvement stores for construction workers or painters). Then she puts daily-sized portions of the hay into brown paper bags. That way the dust and strands of hay don't get around the house and the bunnies get to do some extra foraging. It's worked for her, maybe that's an option for you too.
At any rate, I hope you find a solution so you don't have to get rid of your buns.