Not every ball that hits the dirt is a WP or PB. The key is, why did the runner(s) advance?
Here, the pitch was controlled without advance, therefore there is neither a WP nor a PB.
The runners advanced on the errant "throw" (the roll back to the mound). Score that an error on the catcher leading to all runners advancing and the inning staying alive. All runs that follow are unearned.