I'm not trying to pick a fight here, and I apologize if my words have come across that way.
My point is moreso that damage could have occurred for two dozen other reasons, a dozen of which could place the blame squarely on CGC themselves. Just look at Comics General and how many threads have been opened about Quality Control... allegations of books shipped to the wrong person, books seemingly swapped out, damage caused at the grading facility, mislabels, lack of grader notes, etc...
That's not to say that CGC is at fault here either. It could very well have been shipping damage (which CGC should probably reach out and report before grading). Maybe the OP missed a large defect or didn't secure the package properly for shipment. Maybe this was shipped via UPS or FedEx and it got run over by a truck. Again, we can go on and on about possible causes.
Every month there is another post claiming to have books that have been damaged, misgraded, mislabeled. Some of these are legit. Some of these maybe not so much. As a collector, it's frustrating nevertheless. It would be nice if we had a full checklist of items or a process to offer those people to help them get to the bottom of their problem.