I started bfing DD1 but due to jaundice and very poor advice she was switched to bottles and I expressed 12 times a day for 8 weeks before she gave up bottles completely and was exc. bf. I always pumped 12 times a day barring a short spell at 2 weeks when I was hospitalised and wasn't allowed or had access to a pump for ~12 hours (that really knocked my supply as I skipped 6 pumping sessions!). It is possible to go from no breastfeeding to fully breastfeeding but perhaps not for every mother despite the amount of effort they put in but you won't know until you try if it's possible for you.
I am really shocked that a hospital would say an 11lber can't bf - I have exc. bf a 20m old who was about 26lbs AND a newborn who was 7lb 6oz for 2 weeks until the 20m decided food was good again! (This 20m was DD1 so she certainly took to bfing well!). Very poor advice.
It would be worthwhile to speak to a breastfeeding counsellor about expressing (double hospital grade pump is the quickest and most effective way to express with a pump or you could try hand expressing) and ways to increase supply, also possibly using a Supplementary Nursing System/Lactaid as they deliver formula/ebm to baby while they breastfeed making it more rewarding for them while your supply gets up and running again.
This is a proven way to increase yields while pumping as is this.