I found the drains in my 26RLS under the sink in the kitchen. The cold water drain is behind the panel inside the door, directly below the stove. You might be able to reach this one without removing the panel inside the door, but since it is easily removed, this will make access to it easier.
The hot water drain is accessible by removing the bottom drawer, and reaching around to your left for the drain. It is easily visible when this drawer is removed. Both drains stick out under the trailer behind the wheels on the street side of the unit, and can be very hard to see. The drain valves on my particular unit are the type that you pull up to open and push back down to close.
Thanks to all of you that replied to my original question, the information given was very helpful in allowing me to locate these drains.
2011 Ram 1500 Laramie Longhorn, 5.7 Hemi, 3:92 differential
Tow Package W/Integrated TT Brake Controller
2015 Open Range LT274 RLS