While I have never been an examiner, I would personally verify the county on my own before heading out.  It is simple to do and while it may be the VMS job to send you the right info it is up to you to verify it if you want to or not.  I consistantly get inaccurate orders from lenders and realtors with the wrong county shown.  We also have a few areas in Ohio that fall in 2 counties.  If you are so lucky to have a property straddle the line, would you charge double because you have to go to both counties? 

I feel the pain you suffer by receiving bad info but the VMS are human too and I am sure didn't intentionally send you to the wrong place.  If they have a track record of mis-information than you must verify it before you head out.  Give em a break if it just once or twice a year, especially if your were going to that county to do other work.