Sometimes it's hard to know what to do, even a minor alteration may void a warren-tee, so it's had to know weather or not to touch anything.
At least now you know there customer service sucks, and that will stay in the back of your mind when ordering any other parts again,,,that will come back bite them in the ass!!! DOWWWW !!
If it was me I'd let them know that too,,may not help but at least it will be a "Oh Shit, a pissed off customer talking bad about us on a gun forum",,,,,,,kinda moment for them.
But I'm an asshole that way and would do that type of thing,,,your options may differ. I'm sure your not all that pleased with them anyway if it dragged on so long with no answers.