Transfer of authority depend on your customer. Large civil aerospace companies, such as Boeing & Airbus, tend to allow you to transfer them as they know their own supply chain is good for it.
Is the plane made of Composites?
If it is...then fatigue loading has very little impact on the structure. Fatigue stress calculation are normally not performed on Carbon fiber components due to it's great damage resistance. Up the composites.
If it is not...then they should have made the rig...
MRB engineers are certified through your employer under the authority of the customer. When starting out working in MRB departments you will complete repair schemes and stress analysis' which will be signed off by the lead MRB engineer until they think your competent enough.
Then you should...
Analysis & Design of Flight Vehicle Structures by Bruhn is by far the most widely used Aircraft structures book. I have used it nearly every day in my stress engineers training.