It almost always ends badly.
You have begun to see things they are not ready to.
And they are always right no matter how wrong they are.
At any rate if you really must...
Never meet with more than one elder (3 is always a Judging Committee, no matter what lies they tell you to trick you into attending).
Only meet with this elder if he agrees to your mom being present, and that the purpose is for you to ask questions, and for him to provide satisfying answers.
Never allow him to ask questions and put you on the back foot and on the defensive.
Keep asking him to clarify and prove from scripture.