There is some fiber that is in peanut shells, but it is best to stray away from eating the shells. The outer shell will contain dirt and particulates that you can never completely remove. If you are looking for high fiber, eat fruit such as apples, blueberries or raspberries. These all have more fiber than peanuts.
There is absolutely no nutritional value. Your body is incapable of digesting the cellulose that makes up the penut shells. You are just feeding yourself volume that will come out the other end and risk of bezoar.
The consumption of peanut shells by humans is considered not only low in any nutritional value other than fiber but in some instances, it can lead to the person absorbing dangerous fungi and toxic metals as peanut shells have an ability to absorb these metals through rain and waste water.
There is no nutrition value to penut shells other than the fiber you mention becuase penut shells are made up of cellulose which is a polymer that your body is not capable of breaking down to absorbable nutrients. I suggest you get fiber from a different source as the shells may lead to a bezoar.