I feel for you Nick. I was awarded White Maria yesterday after completing all the quests. I moved her into my formation but didn't gear or rune her up. Thought I'd wait to see if she "stuck around". She didn't.....but I lost nothing.
I don't know what to say about the repayment for your troubles. You have been severely ripped off! Perhaps go back to them and ask for more........... Personally, from what I've read in this forum, I'm surprised you got an answer from them at all.
But let this be a warning to all future players who complete the quests and end up with White Maria. She is corrupt!