At what point do you think punishment is warranted when companies or individuals break regulations resulting in people being placed at risk? This isn't software where the impacts are some user inconvenience and maybe a bit of lost revenue. If this incident had gone just a little differently it could easily have resulted in deaths, people receiving massive radiation doses, or even hundreds or thousands of people getting enough exposure to raise their risk of cancer. Regulations around handling radioactive material are a lot like aviation regulations, they tend to be written in blood.

This is a short list of major radiation exposure incidents in the past few decades:

https://en.wikipedia.org/wiki/Ciudad_Ju%C3%A1rez_cobalt-60_c...

https://en.wikipedia.org/wiki/Goi%C3%A2nia_accident

https://en.wikipedia.org/wiki/Kramatorsk_radiological_accide...

https://en.wikipedia.org/wiki/Theft_of_radioactive_material_...

https://en.wikipedia.org/wiki/Acerinox_accident

https://en.wikipedia.org/wiki/Samut_Prakan_radiation_acciden...

https://en.wikipedia.org/wiki/Lia_radiological_accident