In the hospital...
Elder Lu was resting when Grandma Zhao Shuang was talking to Lu Qiang on a cell phone about finding the file in the safe and telling him about the password. Once she hung up the call, elder Lu, who was sleeping, opened his eyes as he overheard the conversation.
As he was sleepy and under the influence of medicine, he didn't get what exactly she was talking about so he asked, "What were you talking about? Which safe?"
"Doctors need your old reports when you were unwell in the past, so I asked Lu Qiang to get it from our room. He couldn't find them out so I thought it must be in the safe with your other files so I gave him a password to open it." Grandma replied calmly not realizing she had done something wrong.
Though elder Lu was sleepy, hearing it, his sleep went away. "What? You gave him access to the safe?" he exclaimed being panicked and pressed his chest as he felt the pain.