Originally Posted by
FinnishFlash
This might not help you in any way but I have several times tried to use my corporate rate and the marriott site says something like "rooms for this code are not available" and still offers the same room type - most often standard in my case- with way higher price than my corporate rate. I have never called and tried my luck thou, just stayed elsewhere. Maybe they only honor corporate rates as long as there are many enough rooms of that type left?
I've only tried to call once when my corporate rate was not available but standard rooms were, and was simply told that there were no more rooms available at the corporate rate. Seeing as how the corporate rate is often much lower than the standard rate, especially in OP's case, I understand why they might put a cap on the number of people that can book that rate. And in the one situation I was referring to, I know others had booked that rate because one of them was my boss.
As far as I know OP is SOL, but as Roger said I would probably keep checking back online.