Scratch that first scenario. How about instead CC has ended up with Suzaku instead of Lelouch in this verse? Why? Because of whatever was going on with that whole resonance thing between Suzaku and Geass in S1 that was promptly dropped in R2. If canon can be vague, so can we! Of course, Suzaku also has Geass~. I'll let her explain what Suzaku's power would be.

You're lucky Suzaku has a soft spot for girls, C.C.