IST, the funny/sad thing is that recently I had the same issue. I flew into a station that TK barely serves and my bag was badly damaged. Not only were there no TK people around, but all the third party desks were closed as well (Swissport et al). I actually went upstairs to the check-in desk to be told that the person who could deal with it was "airside" dealing with the outgoing flight. So what did I do? I took several pictures of my damaged bag with the check-in desk in frame, as well as some outside identifying the airport.......... Let's see what happens!