j57ltr is right on the money. RoHS is a pain but some oem corps wont look at you twice if you dont have it, especially europe and medical corps. i found soem vendors were passing off LF and PB components as the same. the end caps on the components wont take so well if your using a PB solder with LF components. the fact the solder pad resembles the shape of the end cap may indicate that this has happened, or handling contamination. not sure if a tvs is a moisture sensitive device in storage though? very strange. good luck with the RMA guys.

easy as...123revo