Council of Elrond

I just tried to build a fallenwizard deck that uses one copy of the wizard in the main deck and one copy in the sideboard. Gccg-decklegality-check tells me that i cannot include fallenwizard characters in the sideboard.
Disappointed as I was, I started looking around for a rule/ruling/whatever that says so. But without success! Can you help me?

I'm not aware of any such restriction; I know that the GCCG scripts are generally good but at times cannot handle more bizarre situations.

well, that is exactly the answer i wanted to hear!

GCCG also does not like a Balrog sites in non-balrog decks (some may be legally included in such decks).
At least it was when I played at GCCG last time (some months ago).

The same problem with agents counting ag. the haz limit. In a FW-Deck agents only counts as characters.