I can understand being upset, Disney did goof up!
I've worked for a res center, taking hotel, car, tour reservations etc. for a travel wholesaler that specialized in Europe. I took the reservations, but a differant department all together actually handled the mailing of confirmations, dcouments, etc. If the document department didn't see any notes I might have made, they'd often goof and mail things to the wrong place. I'm sure that's what happened here. The res agent you spoke with made every effort to document and flag the reservation, but someone else down the line made the actual error of not following the instructions to NOT mail the confirmation to your home.
Yes, Disney goofed, and I think you do deserve some gesture of good will (conceiarge is a stretch IMO, but whatever). It sounds to me, though, that you are blaming the res agent you spoke with, when I feel it was another area's mistake. She promised something that Disney as a company should have delivered on, and she made the promise in good faith. You're making sound like she promised something she knew Disney couldn't do, and was just telling what you wanted to hear. Basicly, I think you're blaming the wrong person.
Anyway, try to not let this ruin your trip, you still get to go to Disney!