Thanks on her behalf for taking her in. Ducks do much better with duck company. The thing to watch out for is an aggressive drake (ain't it one thing after another???) In fact a general rule of thumb is if you have one drake, get three to six (!) female ducks. Apparently many drakes just - well - can't control themselves.
That does not mean there are no sweet drakes, or that a pair won't work. But I have read of more cases of one to one not working than working, seems to me. In any case, a duck who is over-mated doesn't care about statistics. So you need to watch closely and introduce them s l o w l y.
Also, the stress of a recent upheaval could affect her laying. Ducks have emotions, and that affects them in all kinds of ways.