Buy one, send it to a reputable carbon repair shop, and forget about it.
I am lucky enough to have two shops near me. A bike of my wifes has been to one and a bike of mine has been to another. When they repair the frames they come back stronger than new. Now, this isn’t always a positive thing as it can alter the frame flex depending on where the repair is. But, for the right repair or for a trainer bike who cares. It can save you thousands of dollars over replacement.