Well are you still losing coolant? Im sure they rplcd the egr for egr codes and Ill be honest,if you werent complaining of losing coolant along with the smoking concern which they would relate as a driveability concern they would address it as a driveability concern(I.E. pull egr codes and put a valve in it). Problem is that if you are losing coolant then its obviously going somewhere(most likely through the egr cooler and coking up the valve). The problem is that working for ford or any dealer for that matter is we are not allowed to "sell warranty",(fix stuff that the customer isnt complaing about). That being said, your valve very well could have been coked up(slightly wet/carbon sludge) and the tech might have just slammed a valve in it not correcting the root cause(not necessarily his fault either). Lets face it you guys know as well as I do these 6.0's build up lots of carbon in the egr and intake passages thats why we have so many egr concerns,and yes it does go back to fuel. Not the owners fault, but these engines were designed and are Calibrated to run on high quality fuel and have minimum idle time. Its not Fords fault either-you can thank the mothers of america and the epa(same thing) for this. Ford and Cat,Chevy ect are all held by standards and are all going through the same problems trying to make perfume smelling trucks. Well anyways im getting off point but the carbon issues we are having along with the egr coolers of the 04+later 6.0's= coking deposits which can lead to lots of issues including repeated egr failures, and excessive blue/white smoke ect. Your best bet having spoke about the coolant loss before is to keep an eye on the coolant level and check for overflow evidence of the degas bottle. Any coolant concerns and take her to the shop and Specifically complain as such.
Fell off, kinda like the cat plugged up!
The EGR valve is in front and to the left of the oil filter right? I will try this tomorrow. 
