When an LQA assessment is discarded, the action is irreversible, and it is not possible to restore it. There isn't any option to prevent linguists from discarding it.
There is only a warning displayed when clicking on Discard button, mentioning that this can't be undone.
Add an option that PM can enable/disable like "Linguists may not discard LQA assessment".
This will prevent linguists from accidentally discarding LQA assessments.