You may have to slow down the number of changes you are making. It is best to make one change, stick with for at least a week or 10 days and let you body adjust. The bacteria in your colon need time to adjust especially when you are changing sources or amounts of dietary fiber. Sometimes with changes or increases in fiber you may experience an increase in bloating and gas for a few days. You have to let time pass before making a judgement.
Are you taking 2 teaspoons of Benefiber per day? I believe the label says 2 teaspoons three times a day.
For IBS-C you have to get your dietary fiber intake - soluble and insoluble fiber - up to 30-40 grams per day or even higher. So source suggest for IBS-C you may to get up to 50-60 grams per days of dietary fiber from your diet. Taking 2 teaspoons of Benefiber three times a day only gives you an additional 10.5 grams from SFS.
You don't have to be stuck with Oat Bran and Applesauce. If you think oat bran is good for you then buy pure oat bran add a small amount (1/4/-1/2 teaspoon) to regular oatmeal and add berries or banana.
Add more probiotic is not likely to gain you a significant improvement. And Jarro-dophillus while it is a good general probiotic it has not been shown to be effective for IBS.
-------------------- STABLE: ♂, IBS-D 50+ years - Science of IBS