We do not accept plant samples for testing.  We do not have enough information to diagnose the problem. How old is the plant, site conditions, planting techniques, etc. When stressed by these issues Azaleas can be susceptible to possible root rots and canker diseases ( Botryosphaeria Dieback).   Azaleas grow best in morning sun and afternoon shade in a well drained soil. Check the drainage in the area.  It looks like there is a lot of mulch around the base of the plants. Make sure mulch is no thicker than several inches and keep away from the base of the stems.  All you can do is prune dead plant material and water during dry periods. See our publication on azaleas for more information http://extension.umd.edu/sites/default/files/_images/programs/hgic/Publications/HG51_IPM_Azaleas_and...
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