So typical of Democrats.so many questions. we will need a special prosecutor to get all these answers
You can easily imagine what happened.
Biden didn't box anything, his staffers did.
The staffer should have notified someone the instant s/he saw an SCI document - but on the other hand s/he may not have known what s/he was looking at, and even so may not have cared. Probably figured someone else would pick up on it later.