The storm never did make landfall and that helped a lot, though there is beach erosion for most of the coastal areas. The area around Morehead City to the more southern of the Outer Banks seems to have taken the brunt of Ophelia though there is some spotty damage all along the coast.
My understanding of why the parishes that were most likely to be affected in the storm were excluded in the federal declaration was that the declaration was only made to facilitate the coordination of FEMA and state and local authorities outside the projected disaster area to set up shelters, set up command posts, bring in disaster rescue teams and pre-position supplies and equipment in a circle around the projected disaster region.
FEMA is not a first responder, but this move supposedly would have made it easier for them to respond faster in this case where the damage to the area had the potential of being catastrophic. State and local officials followed normal procedure and were in charge of preparing the other parishes for the hurricane and evacuating them. That is not, nor has it ever been, FEMA's job.