Too bad I know virtually nothing of interest to you.

Just this : please note the firm name was IG Farben. It was dismantled after WW II because big German "Konzern"s were accused of having helped Hitler to come to power but today they have been re-created and beyond.
In one issue of the wonderful French review "Icare" a veteran mentioned that on some French airfield 1940 a recce-Spitfire was kept in a hangar which was "severely guarded". No more details. This is not much. If you want me to I'll give you the issue number etc.