If ever Harry might have released his wand from shock, it would have been then, but instinct kept him clutching his wand tightly, so that the thread of golden light remained unbroken, even though the thick gray ghost of Cedric Diggory (was it a ghost? it looked so solid) emerged in its entirety from the end of Voldemort’s wand, as though it were squeezing itself out of a very narrow tunnel . . . and this shade of Cedric stood up, and looked up and down the golden thread of light, and spoke.
I know the author is trying to say he would have been dead. but does "then" has a certain depressive meaning to represent those things in these kind of situations?