Perhaps "hoisting the elders with their own petard" will do the trick; quote Matthew 18:15-17 -
"Moreover, if your brother commits a sin, go and reveal his fault between you and him alone. If he listens to you, you have gained your brother. 16 But if he does not listen, take along with you one or two more, so that on the testimony of two or three witnesses every matter may be established. 17 If he does not listen to them, speak to the congregation. If he does not listen even to the congregation, let him be to you just as a man of the nations and as a tax collector".
Ask them why they are going beyond what is written by listening to an accusation from one witness - before that witness has approached you - and preventing that "witness" from applying Jesus' precise directions concerning a sinner, as well as denying you the opportunity to discuss the matter with your accuser.
Inform them that you will consult with a lawyer, after which you will report the elders' actions to the Branch Office Service Department, to establish by whose authority can the elders try to bypass the scriptural directions.