Subscribe by message id

The cFS software bus routes by message id. An application publishes a message, and every application that subscribed to that id receives a copy. CI_LAB publishes commands. The IMU publishes its own telemetry. TO_LAB is the pipe to the ground.

The IMU app is subscribed to the command id, which is what lets it hear commands. TO_LAB is subscribed to that same command id, so the ground pipe is full of commands and the IMU stream never leaves the spacecraft. Point TO_LAB at the IMU message.