Have never worked for a fully legally dispatched airline, with licensed Dispatcher as in this case.
It has always struck me a slightly squiffy that a guy who stays on the ground can make and overrule the operating Captain, from what I have been told by US pilots.
In the UK and ME there is an ETOPS preflight release box in the Techlog. Obviously a DO NOT MISS signature acceptance preflight.
Do the non ETOPS and ETOPS aircraft share a common techlog page format? If so that is a real man trap that can be easily rectified.