Americas play-ins

Can someone explain to me how it works?

1 of the 3 make it to playoffs, all play eachother, if a team wins both of their games they are guaranteed playoffs, if theres 1-1 ties then prolly round differential and/or h2h

Single round robin, top team goes to playoffs

3 teams
2 bo3 per team
each team play against the other 2 teams.
a total of 3 matches for all teams combined.
either the team going 2-0 qualify or the one who wins the tie breaker in a 1-1

how come pacific play ins bo1 but americas is bo3