The "heist" was actually a complex revenge and insurance scheme:
During the chaos of the hazmat response and a subsequent breach of the vault (necessitated by Hen becoming trapped inside), a large sum of money and several diamonds are stolen. [S2E15] Ocean's 9-1-1
Died from an actual allergic reaction to the venom. The "heist" was actually a complex revenge and
Station 118 arrives to find several victims, including Franklin and a money courier named Billy, showing symptoms of what appears to be a chemical exposure. [S2E15] Ocean's 9-1-1
Detectives interrogate the members of the 118, probing into their personal lives and financial struggles—such as Eddie's money issues and Buck's living situation—to find a motive. The Resolution (Spoilers)