Judging from your above comments on photo #1 you seem to assume that it was taken in Wilmington and that Mrs. L. Greer (now identified as Laura Petrea Andersen, married to Lee Jackson Greer) is one of the persons on the photo?
The post card was sent (or was foreseen to be sent) from NY to Wilmington NC. When was Magda in NY? She arrived on May 15th,1915. What would be more natural than sending a post card in advance to her host family telling them that she had arrived in NY?
The photo could be taken in NY, but I don’t believe that. It looks like a set up with family or friends.
Could it be taken in Denmark? In that case it might show Magda with one of her younger step sisters and her step mother. The step sister Ebba would be 17 years old, so she would fit as the middle person.