Well, I came up empty handed in my attempts to get detailed tech information on the 2.5 turbo-diesel, but I do have some ideas based on my general diesel experience and from your description of the problem.
Diesel fuel is VERY prone to pick up contaminants and especially water... most diesel configurations have some sophisticated filter systems to help deal with this... but good maintenance calls for the occassional adding of a can of diesel fuel conditioner to the tank, to help remove water and contaminants. In severe cases, the entire fuel system has to be torn down and cleaned, including draining and flushing of the fuel tank... and ALL filters should be changed.
Since they force flushed diesel through the system and got you running again, I am inclined to believe you have a dirty fuel problem. I would recommend they again flush your system, but also drain and flush clean the fuel tank AND change the filters... Have them capture some of the old fuel from the tank in a quart glass jar, and have someone examine it for evidence of contamination... water will separate and collect at the bottom (unfortunately, water does not separate from diesel as well as it does gasoline... that's why fuel contamination is such aproblem!)
And since the problem didn't come back until you refueled, I'd make sure the new diesel fuel you get be checked BEFORE you put it in the tank!!!
Finally, get in the habit of adding fuel conditioner periodically to help keep this problem from coming back too soon. Ask one of your mechanics about that, or collar a truck driver and get his advice on the subject!
Good luck Hellie11, don't be shy to ask for more help or post a comment, and if you need, you can e-mail me directly at firstname.lastname@example.org