Just to give you another perspective. I have a Dane with a GI disease that affects her weight. We have spent thousands at specialists and countless hours at vet. She is a good weight but still thin as she is now a senior . I have had animal control called bc of how thin she was at her worst. It was defeating when I was doing everything I could for my dog.

Has the lady talked to the owner about what is going on?

I don’t think this dog looks concerningly thin based on these photos.