He is right, but they did spend and borrow years in advance to put manufacturing all over the world and near to their patients and then they had to maintain those facilities at GMP level, staffed while they re-ran their trial. But more importantly then at the end of it all, they did not make batches at once or even contemplate that multiple shots would be appropriate. They made it one shot at a time, an incredibly wasteful and expensive proposition which did not set them up well to compete with an already good range of treatments that mostly delivered the same or better, with less coat.
Their manufacturing was legacy and they did not anticipate how they would best be suited to make such a product. This is why NWBO’s batch manufacturing was, in fact, brilliant. Even though they also were manufacturing by hand, they could roll that cost into a batch of injections that can last 2 to 3 years and keep reinoculating patients against their cancer with boosters to keep it at bay as long as possible. A much better approach and one that allows for more vaccine to be made at once for future use.
The answer was not wrong, it could be explained more. Yours was not wrong, other than that it declared a right answer wrong and redirected attention where you may have most wanted attention to be directed, for better or worse.