Feldlazzaret, in Rouen France, June-August 1940

[Rikster]

Can anyone tell me which german units (of any branch etc), were based in Rouen (was a Sani unit/feldlazzaret at Ernemont Hospital). Also which units were stationed In or around the town of Halluin on the Belgian/France border (there were some, and a rather nice little anecdote connected to one of the officers, which is why I would like to find out the unit involved). Halluin is approx 20km North of Lille and a km or so away from Menen. I am researching a story about my wifes grandfather who was colour Sergeant with the Seaforth Highlanders, wounded at St. valery-en-caux, hospitalised by the Germans at Ernemont Hospital Rouen, he subsequently escaped and made his way to Halluin, where he had been previously billeted before hostilities. had a few brushes with the Germans etc etc and eventually crossed the Pyrenees and Spain and made it to Gibraltar in June 1941. Eventually returning Home. All this after being posted Killed in action!