1. Disturbing them as little as possible, and without moving or bothering that nest, get them off that cedar ten minutes ago.
Cedar is toxic, releases phenols, and causes short term/acute respiratory and skin irritation, and long-term...liver failure.
2. Sun Seed sucks. Sorry, but it does. Try to find a plain pellet feed (no sunflower seeds or colored bits or other junk) that does not have grain by-products, corn, wheat middlings or any crap like that up front (meaning it's a large quantity of that formula).
3. When you do switch her, do it slowly over a week or so at least.
4. She needs constant access to a good quality grass hay. That means Timothy, or Orchard Grass, or a blend. Legume hays, like alfalfa, can be given in very small quantities as a treat, but are too rich and high in carbs for her staple diet. Ditto on grain hays, like oat hay. Only as a treat.
5. She should be getting a fresh salad every day. If you already do that, great. If not, get her accustomed to it slowly, but she needs those nutrients.
6. Not an expert on baby buns, because I have never bred them, nor will ever, but those babies look over a week old to me. How were they not discovered sooner? Are you sure there's only two and no dead dudes covered by any debris in the cage? (Sorry to be gross, but I'd rather throw it out there, to prevent disease and infection, just in case, as I'm sure you're trying not to disturb Mama.)
7. This site, while some of the articles badly need updated, is still by far the most informative I've ever run across, in years of rabbit rescue. Change the drop down menu at the top of the page for whatever you're looking for--medical or care or housing, etc.
Rabbit References - Health and Medicine
8. If you can get 'em to talk to you, and are ready to do some serious "mea culpas" for the accidental breeding, you could contact a House Rabbit Society chapter near you and get more advice. They often have pregnant rabbits come into rescue, and may have an experienced foster who can guide you and advise you.
http://www.rabbit.org/chapters/index.html
9. Your "other girl" Holland Lop was likely mis-sexed, and is the babydaddy. But, that said, make 217% sure you don't have any flaws or loopholes in your bunny segregation system, as your girl can become pregnant almost immediately following the birth of these babies.
I think that's enough to throw at ya for now, but you're welcome to ask more questions as they arise