It's not guaranteed, but there's always a chance to get caught when you use a packet spammer. In this case, I believe standard protocol would be to remove your badges and replace them with the cheater badge.
is it possible to get the chaosshaper/paladinoverlord etc. (the donator classes) through packet spammer?
Every now and then they'll slip up and it'll be possible to get access to shops you shouldn't be able to, but if you take advantage of that you'll most likely be banned. With those two specifically, no, you cannot.