All teacher that will judge you all in the oral test are AFS volunteers. It doesn't make any sense even all teachers are from one place but they're still different peoples, if its differrents it's impossible to judge you all by the same average for all judges. It's impossible also that only one teacher will judge you all for AFS exam, this is one of the point you have to understand.
*If you can't even understand this small point how can you gonna understand a lot more things that are absolutely differrent from yours in others countries*
Relax be who you are, try your best
ACT AS A GOOD LEADER BUT ALSO AS A GOOD FOLLWER