Lisa pulls out the thick electronic device from between her breasts (shown in close-up). However, she is only wearing a nightgown without a bra: there is no way that item would have stay in place and not fallen down, since there was nothing (no bra) to retain it there. Furthermore, her matching periwinkle nightgown shows no bulk there, when she is shown walking across the halls---which means the device was simply not there, until it "magically" appeared for the close-up retrieval.
Lisa is empty-handed when she is walking from her bedroom to the computer room. Yet, when she gets there, she has an electronic device to unlock the door and a computer disc.
Michael gave Lisa Fanning the items she uses in the computer room (electronic door opener and C.D.) Her husband has been established as very controlling. Yet, she carried those items into her house without him noticing but he has been shown calling her whenever she returns home and checking her out. Thus, how she would have concealed those items makes no sense.