I don't recall us having Alex Boys on our ban list either. If it's not on our ban list, you're good to go.
Every once in awhile we have an uploaded video with younger-appearing actors – if other users question it's appropriateness on the site, we'll research it. That's one of the reasons it's important for uploaders to submit basic information about their upload. If upload in question comes from a general tube site and/or we are unable to identify it as originating from a studio with age compliance policies/reports of misuse, we will remove it to err on the side of caution.
Reviewing the AlexBoys site and doing some general research into any reports of underage actors, it appears good on our end. It's material from generic tube sites that are usually more of an issue.