Grinding veggies is required because they don't have grinding surfaces on their teeth so the plant membranes aren't broken down. They eat the partially digested stomach contents which has already been chewed. Grinding is the chewing part:). Their digestive tracts are very short so they can't really do anything with it if it's given to them whole.
If you feed dry food I don't know that I would supplment with a vit. min. sup. They put so much of that in foods already you will be over loading them by adding anything.
Also, if you feed dry don't add any more grain. They get TONS of that in the dry already, I really wouldn't add rice since that's the main grain in Canidae. The whole point of raw is to get away from cooked grain, they can't really use it. While you're at it I would avoid corn as well. Raw, cooked, ground or whole. They don't do well with it, they love it cuz it's very sweet but I would think twice about adding it. Corn, wheat, rice, soy are the main grain fillers used in pet food, dogs and cats both are developing tolerance issues with these grains.
To comment on the cats who went blind when fed vegetarian........... that woman was a complete IDIOT. If you read a bag of cat food they ADD teurine because COOKED meat has none in it. They have to have it for propert heart function and vision. Pet food co's found this out the hard way 30+ years ago when cats dropped like flies on commercial foods. We are suppose to be the more intelligent species, I seriously wonder sometimes.