In your first post, you described the eye as "glossy" and then said the guy you bought it from said that is a common thing with pieds.
Here's my question, and the answer may be important. Did you simply describe the eye as "glossy" and let the seller make his own conclusions about what you meant? Or did you show him a picture of what is going on and after seeing a clouded eye, he says it's common?
When I read your original post, I had no idea what you were trying to describe because "glossy" is a word I might use to describe a healthy, shiny eye. Maybe the seller thought you were describing an extra shiny eye and tried to assure you that pieds have beautiful eyes? And maybe he is actually unaware that the snake developed some sort of eye issue en route?
OR...if you showed him a picture like that one...demonstrating an eye that clearly has something wrong going on...and he tries to blow it off as "common" and nothing to worry about...this would indicate to me that he knew about the problem before he sent the snake out to you, and he is full of BS.