thats why they last, the 30mm grip is a safety feature...they slip out of your hand before anything breaks. get with the program.
Mine is 25mm, it's more ergonomic to hold onto, less energy expended..
30mm is like a tree trunk..
I'll be the last person to recommend a Pryde product to anyone after the amount of their stuff that I have broken but you can't argue with their warranty, it's pretty damn good. They've always honored a warranty claim i've put in that has been due to faulty manufacturing/poor design etc, never had an issue.
Your boom sounds like a straight up manufacturing error but as usual the middle men keep passing the buck, hope you get it sorted.
Agree with all said the trades practices act says that goods sold to consumers must be fit for purpose and there is a test of reasonableness this means that it should last at least a while if that period was tested by a reasonable person. It would be unreasonable to have a boom delaminate after such a short period of time. The shop also can not under the TPA put warranty claims onto the customer, they are duty bound to cover the warranty of the stuff they sell themselves. If the distributor no longer honours a warranty it is the problem of the shop not the customer. Stick by your guns take the boom back tell them you require a refund or will be pursuing them under the terms of the the TPA. It is up to them to pursue the people they bought it off. btw that same set of rules will apply to them and the distributor.
i had an issue with one of my sails and was replaced on the spot after a quick phone call and a picture message..
kinda makes you feel special when it happens 
