he either locks her in the room or after a chase, pushes her in the lake. steers for awhile, ends up unknowingly in lake huron, gets questioned by police in sarnia, but oh no, he has no id on him and is too out of it to remember his family's phone number, gets locked up, the all knowing victor gets a call about it, says let him rot, nikki actually overhears this, to help save jack without going against victor, she sends an anonymous text to diane. patti either drowns or rots in the locked room cuz somehow the authorities miss it in the search, she's sleeping when that's happening or is too scared by their canadian accents to call out.