When I worked there, I also suffered fatigue. I visited my GP, wondering if I had some mild but persistent bug, dietary problem,etc, but she saw nothing wrong. She asked to see my roster and her eyes popped out on stalks. She wanted to sign me off for three months on the spot. I said I'd do three weeks off and then come back to her, so as to avoid the licence and medical being suspended by the CAA. I called in to crewing, citing fatigue. They said they'd put me down as sick. It started an argument that ended in me threatening them with legal action against them personally for libel and fraud if they marked it as anything but fatigue, and that I would be checking.
Half an hour later, I got a phone call form the then new Flt Safety guy who had recently been appointed as part of the Go merger. He was really pleased - the CAA had been following a large number of rosters with fatigue concerns, and unbeknownst to me, mine was one of them. So, that constituted an MOR. Chief Pilot war pretty angry when I cam back, but by that point I had resigned.
Fatigue has been a long term issue in EZY, as have anti-pilot managers. But that is not specific to Ezy - it's endemic to the industry.
My recommendation is that if you feel fatigued, make an MOR, and don't do it through the company Flt Safety office as they may rewrite it or just bin it- it has been known to happen. You'll certainly get a lot of political pressure. Just write it straight to the authority. If the CAA want the evidence, then give it to them directly. And take the time off, citing fatigue in writing. If they are happy to kill you, you owe them no loyalty or "extra effort". All that being "orange" bs only goes one way.