I’ve heard hordes of people talk about how Picea glauca is just not a plant suited for the Southeast. The reason ‘root rot’ most commonly bantered about as to why. Question is, as MOST Picea are grafted onto Picea abies because of its ubiquity, why would that be the case? Picea abies grows just about everywhere. Often without anyone’s permission. Would not Picea glauca grafted onto Picea abies do just fine in the Southeast (apart from the Picea glauca ‘Conica’ plants which tend to be spider mite attractors)?
The root rot may be the main issue for the species, but there could be other foliar issues. Tom Cox, a member here, may chime in, otherwise you may want to contact him. He and his wife Evelyn run the Cox Arboretum in Canton, GA.