Threatening a crew with disciplinary action because they refused to operate into discretion is dreadful.
Presumably the company invoked a 'gross misconduct' clause?
I haven't seen an easyJet contract but would be amazed if any reference to use of discretion was made. Did the CAA Flight Ops Inspector get to hear of this?
The implication is obvious. Crews might operate into discretion when they truly should not be flying.