It's definitely official. I don't have a link but just check your yahoo team or go to rotoworld.
here is statement from rotoworld.com
Royals place closer Dotel on 15-day DL
Royals placed RHP Octavio Dotel on the 15-day disabled list, retroactive to March 30, with a left oblique strain.
David Riske is set to act as the Royals' closer until Dotel returns. The Royals hope to have him back as soon as his 15 days are up, but oblique injuries can be very tricky. Apr. 4 - 6:31 pm et