Looks very familiar...
I bought a package tray with speaker grilles from Yearone. The FLAT box had a bend in it and Yes the shelf was cracked in exactly the same place as yours. Emailed Yearone. "No problem, we will send you a new one." A new FLAT box arrived. It had a bend in it and YES, but this time it was completely off. In the same place! Emailed Yearone. "No problem, we will send you a new one." The boxes even had extra reinforcements.
A new FLAT box arrived and NO, this time it was OK. Could hardly believe it!
Yearone came through and compensated me for all extra cost.
Are there some gremlins cracking the package trays in that spot?