Gone for good: A judicial committee cannot be formed in respect to a former member. And you are legally free to quit any religion at any time you chose. Stop making targets of yourselves - quit the f-----g cult now. Make a written record of the date to show the hounders when they finally track you down - they have no authority over you unless you grant it to them.
I like your tip: It is like over-rolling the cults procedure. Would be possible also in countries were the religion is state approved. Only resign in time at the proper authority.
But wouldnt they "shun" me anyway if i would suddenly disappear. Would my family members than not stop greating and visiting me anyway? I am not sure. It is very risky.