There's no way the CZE captain would choose Rosol I don't think. Based on Rosol's recent results it definitely seems like Wimbledon was a fluke performance - if it was a decisive fifth rubber would he go with the experienced player who has performed for the Czechs or the loose cannon who most likely would bomb? Yes Rosol has beaten Nadal so that would be a factor but more than Nadal himself, Rosol was on another planet that day. In the cold light of day that seems like quite a roll of the dice. Then again, they might think there's no way Stepanek could win vs Nadal - might as well try Rosol - could be a beatdown or everything could fall in place.
Would be quite nice for Nadal to win the fifth point vs Rosol.
I think the Czechs would be idiots to play Stepanek instead of Rosol against Nadal though. Fact is you might as well throw Rosol out there and let him ballbash and see what happens, it's unlikely he'll rise to the occasion once again, but I would still give more hope to that than Stepanek even getting a set.
Anyway would be hilarious to see Nadal showing up for DC just for the doubles. Still a good Spanish team though, I definitely fear Lopez more than Ferrer on a fast court, especially for Berdych.