Realize that a "drain and fill" on an automatic transmission does NOT change all of the fluid. In fact, the majority of the fluid in an AT is up in the torque converter and other locations that don't drain when you just take out the drain plug.
So, you have to un-do the line going to the transmission cooler (in front of the bottom of the radiator), then little-by-little start the car, drain a little fluid from that line, then stop the car, and put fresh fluid in the filler tube. Keep doing this until the fluid coming out that hose is clean and red. Then reconnect the hoses, start it up and shift through all the gears, then top off the ATF level.
Watch this video -- which is a Honda Accord, but the concept is exactly the same -- and adapt the procedure to the Edge. This has worked for every other Auto Trans vehicle I've owned.
I haven't done it on the Edge, but I'm going to soon. I'll take photos and document the adventure when I can.