1. Droid PositionRepublic Resettlement Zone, at the edge of the floor above Olaris Spaceport compound.
2. Droid PositionRepublic Resettlement Zone, Northeastern part, at the edge of the floor in the air.
3. Droid PositionThe Sinking City, Western part, high above in the air, at the highest point of collapsed structure.
4. Droid PositionThe Sinking City, Southern part, above the crashed spaceship engine.
5. Droid PositionTransport Station 5, North from The Tularan Marsh, on a pipe at the first floor of a huge structure.
6. Droid PositionThe Tularan Marsh, Northeastern part, above a crack in the ceiling.
Source: Official MCR-99 droid locations (hidden planetary achievements), MCR-99 Droid Locations post 2.0 on Swtor official Forums. We would like to thank SWTOR community members for all additional information.