In regards to your first question, I suspect you are correct in that your tract of minerals are not within the unit spacing of the well. There are occasion when royalties are placed in suspense awaiting the royalty owner to come forth to claim such but if you are certain there has always been accurate contact information on file at the recorders office then I doubt this is the case. If you want to tell me the legals of your tract I will check and let you know.
In regards to your second question, if your tract is inclusive in the unit of the well on confidential status which is as I suspect a 1280 spaced Bakken well then yes you will receive royalties if the operator has you as a royalty owner, it will depend on the unit spacing of the well. If you want I will check for you and let you know.
In regards to your third question, it depends on the county and formation but in general it is over 90% at this time as most wells are Bakken wells in proven areas. The only major variables on Bakken wells is the production rate, how long it will produce and the decline rate. Most all of the wells are generally producing 4 to 5 months before coming off confidential status.