Definitely talk to them.  Did you leave instructions on when to spray, ie if it gets above freezing stay out of my fields?  When I used coop for application, I left marching orders so to speak.  If they didn't follow them, application was going to be free.

Was this the one at Susank or Hoisington?  Surprises me if it was either one as they are usually pretty conscientious.  If it is one or the other, the general managers are pretty reasonable and I bet they will work with you.