My opinion: It sounds like there are 2+ cameras we are dealing with here: the Ring doorbell camera, which was disconnected around 1:45 am, and at least one other camera inside the house that detected movement around 2:15 am. None of the footage from either of the cameras is available for viewing because it was set to delete every 3 hours.
To me, that indicates that the perp knew there was a Ring doorbell and took action to remove it, but was NOT aware of the inside camera(s) and just got lucky that the footage deleted itself so quickly.