According to a report from Fightful, Roman Reigns made the decision to come back very quickly and Vince McMahon was the first person to know about his cancer being in remission.
In fact, only Vince, Kevin Dunn, Stephanie McMahon, Triple H, and Michelle Wilson knew about this decision until yesterday morning.
This coincides with WrestleVotes tweet from yesterday suggesting that the positive news was being hidden from most in the company.