Your reservation should indicate what type of room your in, and the location of that room. As mentioned, if your staying in a standard room and not in a studio, 1 Bedroom villa, 2 Bedroom villa, or grand villa, you will be in Jambo House (the "main" building). If you're staying in a villa, it can be in either Jambo or Kidani.
The main line at the airport for the ME will only say "Animal Kingdom". All guests board the same bus regardless of which building you're staying in. Once at the resort there will be a drop off at each of the locations.