Yes, it does.
Yes, I guess so. MAVLink inspector is plugged into the serial port.
NEW UPDATE:
I substituted the ODOMETRY and OPTICAL_FLOW_RAD for other message IDs that send similar values, namely the LOCAL_POSITION_NED (vx, vy, vz) and the DISTANCE_SENSOR (current_distance).
The first one works fine, but the distance from the optical flow assumes big random values, although it should have a maximum of 255. Only very rarely the sent values make sense. This problem is the same as this one that I had some time ago, for other message IDs, for which no one answered me.
Any sugestion?