Along with the previous advice if you get your appeal then you should tell them you didn't know you could get DF'd for having doubts. (It says in the Elders book to treat such ones that doubt with mercy)
and that you only sent the UN thing as it had stumbled you.
The tact to take is being stumbled by the UN and having Doubts. Does that make you apostate? No. Tell them of course you want and are trying to believe that the WT / FDS are God's channel. How can they help? Why didn't they help?
It's your only chance that I can see as a person who has sat on many JC.
ADDED: I know this doesn't help, but I'm really pissed off in your behalf. Jesus do they need to control our every thought and feeling. Peer into every depth of the soul to see if any "disloyalty" exits. Perhaps a little burning at the stake to make you see the err of your ways in doubting the FDS. This is nothing more than an Inquisition to rid the heretics. I am very sorry for you and scared that someday the same may happen to me.