Minecraft how to use a legit account to play in a cracked server?

Is it possible? My friends account is not legit so he plays in this cracked hunger games server. I actualy bought the game so when i try to get in that server it says "unknown host"

if there's no possible way, is there any good servers to play hunger games in 1.7.10? I couldnt find any

also, don't now if this helps but the ip of the cracked hunger games server my friend uses is

Guest

I'm pretty sure that if you want to join a cracked server you need to use Hamachi; From past experiences, that was the only way I could ever do it.

Mike