Let's not belabor the conversation, but I think there were more organizational factors in play than that. Most obvious, think about the damage to the brand if consumers associate it with cyanide (of all things). The only "value" at play there was organizational and career self-preservation for the people responsible for responding to the incident. I highly doubt there were any noble impulses or high-minded values involved.

I don't have the case study details in front of me, but just as an aside, companies can be sued and will lose if the plaintiff can prove they were negligent; for example, not taking reasonable steps to prevent tampering.