If the “right” person was under hospital care, and the “wrong” person is found and return in their place I imagine the indicators in their hospital care would be pretty clear they have the wrong person.

• “This patient’s blood type is different”
• “The labs on this patient are coming back drastically different than they were from last week. Last week this patient was pre-diabetic with no hypertension, and now they have no pre-diabetic indicators and are in Stage 2 hypertesion.”
• “This patient gained a 40 year old tattoo in less than 24 hours.”