If you can't trace the problem (camera, lab, handling etc) send it back to Kodak; there could be a manufacturing problem. I've had a similar problem with another brand of film which had unexplained scratches which ran parallel in a non-linear manner on the base side (which in 120 is next to paper). I returned my negatives with a full explanation (camera, process, equipment used etc). The company was very helpful; they investigated the problem, said that they'd never encountered the specific problem but said "it could be our fault", and sent me some replacement films with some extras for good will. Mind you, I had a batch of 10 120 films worth £38 but that's not really the point; there could be more scratched film 'in the wild'. So yeh, send it back IMO.
Cheers,
kevs