Damon Dash criticised the couple after his daughters and Roy were harassed on social media over the speculation.
“They should have stepped up and said something,” he said.
“Adults can go and harass a kid on behalf of an R & B singer? The trolls should have been put in jail for that, it was crazy.”
Roy denied rumours that she was the woman ‘Becky’ referenced in the song ‘Sorry’ about infidelity.
The fashion designer became the centre of rumours after she posted a selfie, hours after the album dropped, that appeared to be a response to the description.
She captioned the now deleted image: “Good hair don’t care, but we will take good lighting, for selfies, or self truths, always. live in the light #nodramaqueens.”
Asked about the rumours of an affair with Jay Z, which Roy has denied, Dash told the MailOnline: “I don’t care what Rachel did, I don’t agree with a lot of things she does.”
At the time, Roy made a statement denying the theory that she is ‘Becky’.
“I want to put the speculation and rumours to rest. My Instagram post was meant to be fun and lighthearted, it was misunderstood as something other than that,” she said.
“There is no validity to the idea that the song references me personally. There is no truth to the rumours.”
She added: “Consequently, online haters have targeted me and my daughters in a hurtful and scary manner, including physical threats. As a mother – and I know many mothers would agree – I feel that bullying in any form is harmful and unacceptable.
“I would hope that the media sees the real issue here – the issue of cyber bullying – and how it should not be tolerated by anyone.”