I downloaded your model and after several attempts, I did manage to have all four 5-pt patches work. I have found (and this is not very scientific) that if I have several 5-pt patches that need to be "patched," and one patch is not working, switch to a different patch. In other words, if you have 4 five-pt open patches, labeled A, B, C, D and you are unable to patch "A," then move on to "B", etc. until you have success. Then with the remaining ones, keep switching off until you get another one to patch correctly. It has worked for me. You still may have to try several times, but did get all the patches to work. If you want, I can send you the bridge2 model that eventually patched.
I was glad to be able to test my theory on someone else's model. As I said, it's not very scientific, but it seems to work for me. Good luck with your cello -- I used to play in a cello in high school, so I'm looking forward to seeing your completed work.