Pure speculation, but I wonder if he had gcp service account credentials sitting around his laptop which applied terraform to the wrong project. terraform apply -auto-approve can wipe out a lot of infrastructure in a few seconds.
Most crimes require mens rea for conviction. That is, the prosecution has to prove beyond a reasonable doubt that you intended to do it. If it's really the case that he accidentally ran terraform with the wrong project/credentials, I doubt he'd accept the plea agreement.
