Martin,
I have the following on the German action:
May 15, noon: Bomb raid Charleville-Valenciennes-Le Cateau-Rocroi area. Also Maubeuge airfield. 27 dead. Seen by GC III/7: 6 platoons of 24 a/c escorted by Bf110 = 2 full Geschwader
The German units were almost certainly KG76 and KG77, escorted by II/ZG76
Cheers, Pieter