It's likely sure, but I highly doubt it. The show is doing well enough already, but having her in the show could increase sales, if they aren't already selling out. But, let's remember the Britney Speaks in Chicago rumors which slowly fizzled.
Britney Spears was offered the 2005 production of Sweet Charity, turned down. Producers decided to close then. The one "stunt" casting I would have loved to have seen would have been Judy Garland as Mame. She was supposted to do it, and everythig was there, but the producers were so-so, due to the drugs/alcohal. Poor Judy
"Ok ok ok ok ok ok ok. Have you guys heard about fidget spinners!?" ~Patti LuPone