Yeah the hoisters that post their gt on here are legit, but there are a lot of people attempting to join their session. That makes it extremely difficult for anybody to join, especially people with bad connection. My advice is to look at the top of the score leaderboards. Look for the people with about 1 day played and are online playing domination. These are the hosters. It is very easy to get into these lobbies. I found one guy and was able to join his session every time with ease. Once you've joined it the first time, just check your recent players to join them again. Repeat this until you are your desired prestige!