In such a terrain the Oto Quintet would be just too much for Kakashi, especially with Kimimaro.
The four of them needed their second Juin level to defeat Genma and Raidou, yet you seem to forget that they were part of Minato's special guard, meaning they're basicly the same as Anbu and have to be pretty strong. On top of that Jirobu, Kidomaru, Tayuya and Sako weren't even wounded after the fight, they just suffered from the side-effects of their second Juin level.
He would take the most of them out, but in the long run I can't see him surviving when Kimimaro, Jirobu, Sakon and Ukon engage him on close range while Kidomaru attacks with his arrows and Tayuya controlls her colosses from a safe distance. Even if he could manage to kill all of them but Kimimaro, which I wouldn't put past Kakashi under the right circumstances, I don't see how Kakashi will defeat Kimimaro.