Numb3rs Slash Ficathons

I think I have an idea, but I'm not sure whether it really qualifies as trading places--it's role reversal of a sort. Don is kidnapped and held hostage because Charlie and Amita are out with each other and Don's still recovering, so Amita/Don trade places as the hostage but all other aspects stay the same. Is this too literal an interpretation of trading places? >.>;