Cloudflare was responsive and reasonable. Verizon was unreachable and deflected responsibility when they finally made a statement. And public shaming does often motivate companies to be more responsive to their customers.
I'm not saying Verizon is perfect nor absolved of fault, but Cloudflare was/is not owed any kind of explanation or assistance by VZ, and it's absurd of CF to still be whining about that fact (as they are doing in some other tweets today). If CF wants some kind of SLA with VZ, they should engage them in a business relationship, not try to publicly shame them.
Kind of similar to a homes association saying “hey that trash on your lawn affects your neighbor, clean it up!”
It’s true that they are not a customer but at that level what they do affects each other, and it’s better to resolve things civilly and privately instead of publicly on twitter.