The sniper sensitivity seems to affect the the aim down sights sensitivity of every gun in the game, atleast it did make the ironsight ads on my MP5 faster when I tried it, which means it should work for every gun/sight in the game as long as we have the fov of those sights. Not sure which sight DPI Wizard used for the calculations but I suspect it's the standard scope for the Blaser/DSR based on the fov used.
The config file location (Ironsight/ini/ironsight_local.ini.) is definitely correct but I can't seem to get the game to read the sensitivity values I put in there. It always remembers the last value I set it to in game and overwrites the config with that. Same thing if I set the .ini to read only except it only uses the previous sensitivity I set in game without ofc overwriting the one in the config.