I've never tried the freeze dried kibble of NV, nor have I ever had an IBD kitty, but I do feed a combination of raw and canned only to my two cats.
I think the reason most people choose to feed raw because they believe it's the most biologically appropriate diet for carnivores, and it closely resembles what they'd eat naturally in the wild (small live prey like mice, small rodents, rabbits, birds, etc). The whole issue we have with kibbles are that it's just so dehydrating for a cat to consume, and causes a whole variety of medical issues later: FLUTD, kidney disease, diabetes, and even IBD. (See link below) Kibble has only 10% water, canned has 78%. Cats that consume raw also benefits from a high protein diet that has very minimal carbs and "fillers" you see in the dry. It's also high in moisture, similar to canned. Cats typically get all of their moisture from their prey in the wild, so they have a very low thirst drive to begin with. Our domesticated felines are also descendents of a desert
Kibbles do not have any effect on cleaning teeth, I'm sorry to say. Vets who say this are relying on outdated info. Raw meaty bones will clean teeth nicely; imagine a cat's pointy teeth eating kibble vs gnawing on flesh of meat and bones--you'll definitely see how their mouths were designed to work!
If you're worried about your kitty choking on raw, cut or crush the wing/neck into smaller pieces. COOKED meat and bones are the only real hazards for choking, and cooking will destroy the natural enzymes and amino acids like taurine needed for a feline's diet, so you never want to cook meats anyway.
I don't have any guidance to give you on IBD kitties, but to me, it makes more sense to eliminate as much "junk" from their diet so you know exactly what is causing her issue. The more ingredients in their food, the tougher time you'll have figuring out what's causing her IBD. I'm glad that she likes the Rad Cat lamb.
Links with info on IBD and raw diet for felines:
Feeding Your Cat: Know the Basics of Feline Nutrition :: healthy cat diet, making cat food, litter box, cat food, cat nutrition, cat urinary tract health
Lisa Pierson's website has an extended article on the dry food, if you scroll to the top, plus much more info. It's a lot to take in, so go as slow as you need to.
Feline IBD: Nature and Treatment - Feline Nutrition
Dry food on teeth:
What Dry Food Does to Your Cat's Teeth - Feline Nutrition
Does Dry Food Clean the Teeth? | Little Big Cat
How to Control Tartar Build-up on Your Pet's Teeth