Is this a CRD or Gasser? There is a difference in how cruise control between the two works. The speed sensor sits on the rear diff....if the speedo works you would expect the cruise control to work but as stated above the Mechanics may have disturbed something or replaced some wiring.
All 2005 KJs have a TSB whereby the rear diff was filled at factory with the incorrect oil...this oil chewed up the sensor. Fix was for the Dealers to drain and clean the rear diff, fill up with correct oil and replace the sensor. Maybe this is why your sensor failed?
Depending on if it is a CRD or Gasser the Brake switch is relevant or there could be failure in the Clock Spring under the steering wheel boss.
We may need to climb into the wiring diagrams.