

The photo looks like an adoration stare. I’ve known multiple dogs that do it. It’s either the equivalent of a loving hug between humans, or an attempt to con someone out of some food.
Dogs are a lot more “in the moment” than humans. They remember traumatic events, but are far less reactive to them, unless something explicitly sets off the memories.
Basically, the dog is either very happy to be spending time with its pack leader again, or just wants the treat they are holding behind the camera.
I’ve known enough actors etc that I would be surprised if they didn’t go all out for the doggos. It might “officially” be a rehearsal, but they are likely putting in as much effort, or more, as a full performance.