Are there no kiosks at SJC? Usually I do my best to avoid contact with any human airline employees for this very reason. If there were kiosks, the OP's friend should have gone directly there and not the counter - even after being denied at the counter, they could have used a kiosk to reprint the BP.

I've been in a similar situation with Delta, and when refused by the agent, I just ignored them, found a kiosk and reprinted from there and went on my way.