A source told The Sun newspaper: "There's been rumours knocking about that Victoria wasn't going to show - but she always made it a priority.
"She was never going to miss the launch and is looking forward to seeing the rest of the girls. The musical is a proud moment for them all. It will be emotional."
The musical is set to open in December at the capital's Piccadilly Theatre and will feature many of the girls' biggest hits.
It had previously been claimed that the musical had created a rift between the girls.
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