Oh, brother. No to that adoption.
First, a male homosexual pedophile (I'm assuming this person is also not committed to abstinence!) is committing criminal acts with some child or children, even if not with his own adopted child. In that sense (criminality) he's sooner or later headed for prison (sooner, we hope) and ought not to be adopting, just as we wouldn't want a known counterfeiter, embezzler or drug kingpin to adopt.
Second, the particular kind of crime he's involved in, involves something deep in his ability to form relationships with other people. He may be sexually aroused by males, but he's not engaging in wholesome relationships with anybody, adult or child, male or female. I say this because pedophilia is a pervasive emotional problem, of which seeking sex with children is only one obvious symptom.
Thirty years ago, some psychologists thought they could treat and rehabilitate such men. Now I don't think anybody believes that. These men are so twisted by obsession and compulsion, they don't even quite grasp that what they're doing is wrong.
There's a really revealing film/DVD out there called "Deliver Us From Evil" about a serial child abuser, Oliver O'Grady. The scary thing to see was how almost light-hearted he was when describing is predations, as if (even after trial, conviction, and 7 years in prison) he still thought what he'd done was kind of friendly and cute.
And not only that: such people are so confused, I doubt any of them are exclusively "hetero" or "homo." The just want sexual gratification with whatever sweet, vulnerable creature they can get their hands on.