Something will surely go wrong here, but I still like it, for a buck or two. Round robin format with several 2 or 3 out of 5's to win also doesn't seem like a bad option.
Also, something more reasonable:
Zvonareva 1.4 (F, Pattaya) France 1.25 (M, Davis Cup) Argentina 1.35 (M, Davis Cup)
Odds: 2.4:1
This one should hit. Might make sense to separately pick France and Zvonareva for substantially more money, as I do not see how these two could lose.
Another thing: might be a good idea to pick Croatia over Japan (Davis Cup, 2:1), and then bet Nishikori to win both of his singles matches, to rack up a guaranteed profit. Because if he doesn't win both of his matches, there's no way the favourite Japan is going to advance here...