If you are looking for an ADR for BOG and are having trouble finding one, don't give up. We just booked our stay a week ago and as soon as I got off the phone with Disney, I looked for an ADR for every single evening we'd be at WDW. I finally found one the evening of the 3rd day we are there. I booked it right away. After a few days of really going over crowd predictors and such, I decided I didn't want to go to the MK that day (we are there for 8 days, but only got 5 days in the parks....no hoppers). So, I started hunting down an ADR for the 2 days that I wanted to be in the MK and after 3 days of looking, finally found one.
People are always cancelling and moving their ADRs around, so you might get lucky.