I doubt that it's rattle can. But you can wipe a little acetone, break clean, or your wifes nail polish remover on a part of it and see. All those solvents will eat right through spray paint but not hurt Cerakote at all.Hiland Arms is there a test to determine if it’s rattle canned versus cerakote?
My guess is they either messed up the hardener ratio or used old expired Cerakote.
Cerakote has a very short shelf life, they say a year but that's only if they store it correctly and even stored correctly it might not last a year.
That's my best guess. I see it a lot from shops that don't do Cerakote on a regular basis, they try to use the big bottle of Cerakote they bought years ago and it doesn't lay down smooth and has kinda a chalky surface to instead of smooth and slick like Cerakote should be.