Theory: "they will be back"

Maddie and Caspian choose to relive their lives in a similar simulation, although David says "they will be back" before Maddie wipes his memory.

My theory is that this is because Maddie has "seen some sh*t". She wants to relive/remember what how she originally felt before inserting herself and Caspian back into the simulation with her family all alive afterwards. It would be hard for her to connect otherwise as god Maddie.

What are your thoughts?