That’s correct. Flight controller is 2.4 and video is 5.8 so it will help in the are of flight control only. I have one - it definitely works to extend range in a reasonably open area.
WRONG ....
Video and camera control / telemetry is 2.4Ghz .....
Flight control is 5.8Ghz.
Sorry mate - you got them wrong way round.
For a CE machine .... best simple combo is :
2.4Ghz to be modified signal by either Magic Power (needs Computer to do it) or as I used ICARUS (uses the Android Tablet you fly with). This puts signal strength to maximum 27db
5.8Ghz to add the Windsurfer parabola reflector.
You should then be able to reach ~2000m rural and about 1000m urban
Nigel