It was previously reported that Kaz, who had to quit the trio for a second year over visa issues, could return if they made it through judges' houses this week.
Kaz had to leave the band after being unable to fly out to America for Gary Barlow's judges' houses in New York.
But although Kaz won't be seen on screen, he's still very much a member of Rough Copy and will be cheering them on from the sidelines.
The group's Joe said: "It's emotional. We believe we're such a strong group. It makes us want it even more and I think you can see our passion. We're missing our third element but we have to keep going because our aim is to get Rough Copy's name in lights. The band is three members, no matter what."
But he revealed: "If - actually not 'if', when - WHEN we get to the live shows, Kaz will probably not be allowed to rejoin the group but he'll be there in the sidelines every step of the way.
"He'll be helping us and guiding us and we'll be doing it for him."
Speaking to the Daily Mirror, Joe added: "Obviously we don't know exactly what's going on in his head but we know he wants to be here.
"But he trusts us and he's leant us his spirit to bring all the way to New York with us and to continue the journey. He believes in us."
The X Factor airs this Saturday and Sunday night on ITV.
Browse pictures of the groups performing at judges' houses below...