In Part 1, Deroux hides Adele in the prayer room beneath the altar to protect her from Asteroth. In Part 2 she is in the convent and available when Ryan storms in.
Marceau says in the station that he suspects Ryan of killing Jack. Ryan wasn't in town when Asteroth attacked Jack, and the flight records would show Ryan was still in the U.S. when the attack happened. [When he makes that statement, he's referring to Ryan's late night visit to Jack, when he is interrupted by the nurses and jumps out the window. He states he suspects Ryan of trying to kill Jack, not actually killing him]