Soak the saffron in a small bowl with 3Tbs white wine for 20 minutes.
In a large pan, heat 2 Tbsp olive oil over low heat. Add garlic and cook, stirring frequently until it softens and gives up its fragrance, but is not browned, 8-10 minutes. Add the remaining wine, then add to a slow cooker.
Stir in bay leaves, tomatoes, and broth. Add the saffron mixture and season with Kosher salt. Cover and cook on low for 3 hours. Stir the broth then add the cod pieces, cover, and cook an additional half-hour until the fish is firm to the touch, but cooked through.
While the fish is cooking, zest the orange, then cut away the remaining rind. Cut out the orange segments, leaving the membrane, and remove the seeds. Roughly chop the orange flesh. Combine the orange zest, orange flesh, bell pepper, parsley, and sherry vinegar in a bowl. Stir in the remaining 4 Tbsp of olive oil. Season with salt and ground white pepper and stir.
Discard bay leaves from the broth.
To serve, sprinkle the orange and pepper salsa over the fish, add the warm broth, and serve.