The boyband are trying to decide whether to hire Williams or their X Factor mentor Louis Walsh for the role, according to The Sun.
A source said: "The boys had a massive wobble over Louis Walsh.
"Louis has management experience but Oritsé has youth and the knowledge of being in their shoes on his side.
"People think Louis is past it for a band like this."
Union J - who finished fourth in the latest X Factor series - recently signed a record deal with Sony.
Williams's JLS bandmate JB Gill won the Christmas edition of Strictly Come Dancing on Christmas Day.
Watch Digital Spy chat with Union J below: