OK, so somebody is going to be replaced by their Mirror Double, similar to Harry Kim in the "Deadlock" episode. But it turns out the Mirror Replacement is actually a nicer person.
Maybe MU Landry will show up and she WON'T be an incompetent jackass who gets herself killed in a stupid and pointless way.
I would find it very amusing if somehow her being very kind and overly cautious also gets her killed.
'Will You Take My Hand' is almost matrimonial but could well be like a parental figure helping or guiding someone younger or in need of help. Given it is episode 15 I'm hoping it means moving on from the war and rebuilding