Silestone Useless Warranty

We purchased silestone (cosentino) (roseville, ca) counter tops for our kitchen remodel from lowes (cotati ca.) on 3/4/2016. After discussing different installation options, we chose to use lowes installer which was counter fit (sacramento ca.). All 3 of these companies knowingly sold / installed an inferior countertop which came with a useless 20-year warranty.
The silestone countertops were installed by counter fit on 3/28/2016.
Fast forward to thanksgiving 2017 - yes, a mere 20 months after the installation. While cleaning the kitchen my wife noticed an approximately 6-inch crack running from the corner seam (were countertops make a 90-degree bend along wall) towards the sink. This spot of the counter top is in what we refer to as "no mans land" meaning the only thing you place in the corner were the crack is located is a picture or napkin basket. No cooking, no prepping, no washing of any items, nothing happens use-wise in this area of the kitchen and there is a visible crack. Just for the record my house was built in 1952 so I am not going to buy the "house settling" story.
No worries I thought (big mistake), we have a 20 year warranty and it has only been 20 months.... No problem - right? Absolutely wrong. This is where all three companies - silestone (cosentino), counter fit & lowes have collected their monies and now do not give two cents about the crappy product and crappy warranty they have sold and installed in your home - that's customer care at its best.
I emailed lowes kitchen design department first 11/27/2017 to report the problem, they emailed silestone (cosentino) which in turn issued a warranty claim number. Silestone (cosentino) advised that the installer - counter fit would need to come out and inspect the crack. No problem, just let me know when and I would be there. Keep in mind this was november of 2017, no one ever contacted me to come out and inspect the problem. I have over a dozen emails for exactly 1 year where I am trying to get some sort of response from any of the 3 companies that profited from this transaction and none of them have responded.

Today I sent yet another inquiry in regards to the warranty and finally received a response from counter fit that the warranty claim had been denied as it was "not a manufacture defect"..... What?...ok...what is it then is my question with no response. I guess a crack in an expensive counter top stone is normal after 20 months?
After reviewing online complaints (complaintboards.com) this seems to be the norm for these folks at silestone......issue useless warranties and find any reason to deny all claims, in my case there isn't even a reason for denying the claim. No one came out and inspected the crack. The claim was just denied after the silestone countertop cracked within 20 months of install. Please stay away from all 3 companies stated above as they all are dishonest companies that need to learn a lesson in customer service and honest dealings. Buyer beware.