I worked at a place where we had a major cock up like this. As IT Manager, I took full responsibility.
I insisted that the production environment should be kept separate, and access limited; but I was overruled by the directors.
I said that the consultants should not be given admin access; but I was overruled by the directors.
I demanded extra backup and continuity resources; but I was overruled by the directors. They also cancelled 3 separate planned DR tests in a 2.5 year period.
When inevitably the consultants screwed up, the entire system went titsup. We were able to get it back up and running, but it took 8 days just to determine the problem. As it was not in the data, restore from backup did not fix the issue.
Shit happens; how you deal with it shows the character of the individual.