Intresting note: the launch parameters the specified under "Last game report" in the crash report are not the ones I set, both in the steam->properties->set launch parameters, nor the ones I selected in the Arma3 Launcher. For example in the crash log there are mods listed that I didn't load on that game start.
(See attached Screenshot, everything not marked was not put in the launch parameters by me and also doesn't show up when I check them)