How do multi-account devices fare under these rules? What if I only have access to account A and not account B? What if unlocking the device requires a securit

How do multi-account devices fare under these rules? What if I only have access to account A and not account B? What if unlocking the device requires a security key that I do not have with me? My intuition is that they'd still treat that as though I was impeding their search, but I wonder legally if it changes anything.