That guy gets more character development than Ensign Mayweather, and we don't even see his face!
I think Captain Boday and Vilix'pran get more character development than Mayweather, and we don't see their anything
At least their lives have developments
in them, or so we're told.
It's a shame we never got the informant's name. There's a Cardassian informant of Odo's mentioned in season seven's Treachery, Faith and the Great River;
Russol. It might be speculated that this is Russol.