Q.Can I Utilize Land Recently Cleared From Raspberries With Orange Rust Fungus For Anything?
I had to cut out a 12×4 foot section of raspberries due to rust fungus. I want to use this space for something productive preferably something that will help fortify the soil against the fungus next year, or a useful companion plant to help my remaining raspberries. Trying to turn lemons into lemonade. The area is south facing 4-6 hours of sun per day zone 7B (PNW).

Certified GKH Gardening Expert
You can, pretty much, plant anything else that isn't related to raspberries in that area. All rusts that affect raspberries and blackberries will be a permanent installment in the soil, and no treatment will kill it off.
Here is an article that will help:
https://www.gardeningknowhow.com/edible/fruits/raspberry/treating-rust-on-raspberries.htm