Carbon can be repaired in theory but it has to be done by someone who knows what they're doing. Carbon gets a lot of it's strength from being a continuoes fiber so any breaks greatly reduce strength. To repair carbon you have to completely sand back area of repair and then clean it well (no dust whatsoever) and use an epoxy resin and more carbon fiber cloth. You also need to have consistant pressure during the curiong time (which can be hard to get on an odd-shaped object like a wheel). It is an itchy, sticky, messy job. To pay someone to repair it will cost quite a bit- you would be better off to start new- unfortunately. The area of repair is likely to be heavier than the rest of the wheel and it could make for a funny wheel rotation. Also you would never put fiberglass on a bike as it has way too much flex and not nearly the strength of carbon. I am a boatbuilder and have done a lot of carbon work and would not repair a wheel.