There were many Daz and Poser models used in this video.
Psst, you may have linked the wrong video since I didn't spot a single Poser/DS item (unless rendering is your leet skillz), but it's a beautiful video. I especially liked the "Write that letter home" and also the kid at 2:55. Thanks for posting it!
Thank you. Yes, there are "effects" scenes using Poser/DAZ models. Some examples:
1.The commander standing in the fog as his soldiers ran by.
2. The gunner on the bomber when you see flashes of flak.
3. The soldiers crawling on the beach as a support aircraft flies over.
All of the objects and scenes in these scenes were assembled from Poser/DAZ artisans. I will admit to some major post work in After Effects.