Perversely, in some very homophobic cultures, men hold hands with men because they are so homophobic that there is not even an insinuation that they might be willing to publicly show homosexual inclinations, so handholding is assumed platonic.
However, I think your (gowld's) comment transfers a lot of cultural baggage and sexual-orientation lingo from western culture in a way that I think is quite rude. Those Sudanese guys weren't holding hands "peversely, because they're so homophobic", they're doing that because that's how they've grown up and it's a totally normal thing for male friends to do over there.