That's because he himself appears to have said to an interviewer he went to Indonesia at the age of two:
You might recall where that article appeared, I don't have the full page.
...although Fred has an alternate thesis with Maya Angelou being the custodian
Not quite. Maya Angelou first appears in this connection when she was in Cairo with David DuBois, working for The Arab Voice, in the same period as Malcolm X made his first trip to Egypt. She then shows up in Hawaii where she apparently stayed with her brother Bailey Johnson, shortly after Malcolm was assassinated in 1965.
Maya and brother Bailey Johnson in Hawaii in 1965
'In the water' (or at the beach) with Stanley Armour Dunham looks to me more like the same summer.
1965 would make him about four. The picture looks older than four and a lot like the school picture at Christmas with the future dentist in 69 in the third grade.
And there isn't any reason to see him in Hawaii in 65 either--Stanley starts school in March of 63--no Barry to be seen anywhere; he is in Indonesia at that time.
It doesn't look to me as though Stanley went to Indonesia until July of 66.