I can`t find rogame, twi, tripwire, red orchestra, redorchestra or whatelse in the registry.
What i could find was another game of steam (arma 3) and when i check that in the registry i find this, "main" D:\Program Files (x86)\Steam\steamapps\common\Arma 3
So, i think for RO2 must be such a line too, but which one?