Chlentzos family in Los Angeles c. 1954-- who are the visitors from Australia?

Three generations of the Chlentzos family in Los Angeles, c. 1954
Front row: Philip Adkins, Keith Adkis, Ann Chlentzos Dryden, Cal Dryden, Diamantis Chlentzos, Yanoula Koulentianos Chlentzos, John Alfieris, Mary Chlentzos Alfieris.

Back row: Barbara Chlentzos Adkins, Steve Clensos, Harry Chlentzos. The two remaining gentlemen in the back row are identified as visitors from Australia. Does anyone know who they are?