Not a good sign.
My guess is that Rush’s treatments have left him immunocompromised and he’s been advised not to leave his house.
And as you may recall his studio is in a commercial building about a mile away because the local government where he lives has zoned against doing any sort of business activity out of your home.
With his compromised immune system and south Florida being a Petri dish for cv I imagine he’s taking every precaution.