First we need to recognize the Germanicon Heer had no intention of employing any type of G1 bayonet and the assessment of different slats on the removal flash hider pertaining to a bayonet is likely a moot point.

The twist on flash hider with the red markings was provided by FM the manufacturer of the G1. The top photo is likely of later German manufacture which simplified the vent cuts during machining (and reduce cost).
There was also another German manufactured flash hider with a simple spring lock to hold the device in place.