I cannot find any information about the flight details in any news article.
There is a graphic that shows the area of fog in the area that night.....with some clear areas surrounding the crash site but with dense fog at the crash site.
If they were operating in the clear areas and then returning to where the fog existed...that could have a bearing on the accident.
The Pilot for former US Army and at some point in his Army flying was assigned to flight duty on Sikorsky Blackhawks.