Worth trying all avenues: try also contacting DXB lost and found as well (they may kick you back to EK since it was left onboard).

I actually got a proper response once after filling out this form.

http://www.dubaiairport.com/en/pages/lostproperty.aspx

(just left a bunch of cash yesterday in a hotel room in KSA and checked out - duh! - only to notice while I was trying to pay for a drink in the lobby before leaving for the airport. Housekeeping guy found it and returned it to reception. He was nicely rewarded).