If some anonymous man in a bar tells you that he's been taking thousands of digital photos of nude men in his basement, that he's stacked them into nude human pyramids, paraded them around on dog leashes while naked, and even filmed somebody else raping a couple of them...do you suspect this stranger of being gay or straight?
If he happens to be a guard in an all-male prison, in a country against whom we are at war, and he had already been up on charges of beating his wife, I would suspect that this stranger was a criminal, doing what criminals do.
He may be gay or straight.
You appear to be saying that a heterosexual could never have conceived of these brutal actions; that only gays would strip prisoners naked, and sic dogs on them.
Is that what you're saying?