Yes, I see that your photo was taken at ZooHistorica last year. However, I couldn't have "checked it myself" as I didn't go inside the old Cattle House on the conducted tour. I stopped to take photos of the Eastern gorilla and, by the time I'd caught up with the party again, you'd already been inside that building so I missed the opportunity to check this.
(I've been inside Antwerp's old Cattle House many times in years gone by. However, on my last five or six visits to Antwerp the building was closed to the public and it is several years since I've been inside.)
I see - sorry didn't noticed that but now that you tells this I remember also some other ZooChatters missed this part of the conducted tour. Also sorry that I can't help you because - as said - I didn't pay attention on any memorials... sorry.... maybe next time.