That image isn't clear enough to date him, and the group photograph 'on the dock' is entirely without provenance, the identification of some members of that group seems to indicate that the photograph was taken in 1970-71 when the Kenyan visited Hawaii.
And once you look closely at the face of the Kenyan in both images, it becomes clear that the black and white image might be a photoshop. How did the Kenyan get to be the same height as Stanley Armour, and who is the young woman snuggled into the man with the numerous lei? Just what are the possibly fake lei hiding?
Nothing is as it seems at first glance. No one has been able to trace the source of that image.
Just throwing a first impression out, that may be stating the obvious, but Obama and Dunham, strike me as being remarkably close to each other in their age, with regards specifically- to the facial aspects.