I was just wondering how you are getting on?
We had a similar problem with ours at the time you posted, and have got it sorted now - we did some swapping (giving a tastier treat when approaching the dog that has a bone) and it really worked well. He doesn't mind being touched now when he's got something good to chew on, I think TBH he'd got a bit paranoid because ds (2) does have a habit of snatching from him.
I got a lot of good tips from the 'Perfect Puppy' book.