He needs to set up his DME reservations this way:
First resort - Yes to DME from MCO to resort; No to DME from resort to MCO
Second resort - No to DME from MCO to resort; Yes to DME from resort to MCO
I've done both scenarios. In 2007 we used DME from MCO only - we flew into MCO but flew out of Sanford so we used a car service to take us to Sanford airport. In 2008 we used DME back to MCO only - we went to US/IOA area, used a car service to go from US/IOA area to POR, and then used DME from POR to MCO.
He may have to call Disney now that the ressies are already set up but I think the to/from MCO options can be selected online if you book online.