I used Guy, Neji and Sai/Kiba (sorry i don't remember wich one i was using when i pässed it), and water clone instead of poison... I saved all misteries for the toad...
After a few tries i noticed that the toad's swipe would hit those with less health so i put my ninja in 1st and last row: clones in the middle as easy targets :lol... I also made sure to use the misteries of those that would be targeted by the second swipe first...

a few tries more, and finally the rng system took pity on me ;P