The reason the answers here are all over the map is because the dub organization is inconsistent in both the application and enforcement of the "rules" governing this situation. In addition, the written rules are purposely vague and their interpretation varies in different parts of the country/world.
Consequently, no one can answer your question with 100% accuracy.
I sat in a KH one night and heard an announcement that so-and-so had been DF'd and everybody in the congo looked around as if to say "Who?"
It turned out it was the thirty-something son of an elder who no one in the congo had ever met, a guy who had left home at 18 and dropped the dub lifestyle. His father had recently learned that the son was a "sinner" of some particularly offensive (to him) kind and would not rest until the body of elders agreed to read the kid's name. They did this based on the the testimony of two witnesses, the father and mother. Never mind that no one knew him - neither as a witness nor in any other way - and the congo did not have his cards (the family moved in long after the boy left home).
This is a rare event, sure, but the point is: Under some circumstances, elders can pretty much do anything they want.