Jenny,
   Check the Yellow Book county lists and you will find notations for the species breeding in Garrett County.  In addition to the locations you mentioned I would recommend the other state parks, Herrington Manor and New Germany, and Mt.Nebo WMA.  You don't have to go that far to see a Veery in summer.  It is a local breeder in the Piedmont inclduing Howard County.  Check with your local Atlas coordinator for some locations there.  They were still singing in Carroll County on Sunday.
   Have fun!

Bob Ringler
Eldersburg MD