Tulisa Contostavlos, Pixie Lott and Olly Murs have been invited to the July nuptials and the couple have convinced each of them to sing.
The pair have also agreed to sell photographs of the ceremony to a magazine in a six-figure deal, The Sun reports.
Men attending the reception have been asked to come in black tie, while every woman must wear a black cocktail dress at the adults-only party.
Invitations to the event are said to be in black and white with a diamanté centre to match the strict dress code.
The Saturdays singer has also signed a deal with clothing firm Lipsy to get pink and grey tracksuits for her closest friends to wear as they get ready.
The couple have asked guests to make a donation to charity rather than buy wedding gifts, with Wiseman supporting Marie Curie Cancer Care and Humes choosing his own JLS Foundation.
"Marvin and Rochelle have gone all out for their wedding - it's totally over the top. But they're keen for some charities to benefit from the big day too," a source said.
"So if people do decide they want to give them something, they'd much rather it went to less fortunate people."