...having received an unsatisfactory response
In whose opinion? Her's or the Captain's? It's NOT her call. The flight crew were not incapacitated and were working on the problem. Passengers were disembarking so we are not talking about a Flight 163 scenario. The doors were open, there was no smoke.
To me, it appears that even with the flight deck door open and being fully aware that the crew were working on the problem, the SCCM still decided to order an evacuation. At that point, she was then NOT part of the crew and effectively a loose cannon and certainly not working under the Captain's authority. Her actions actually undermined it. Maybe it was panic or even poor training. The AAIB report states
"However, the flight crew were not incapacitated and it is evident that verbal communication with them would have been possible had the member of cabin crew persisted." No medals should be awarded for unnecessary and dangerous decisions taken in isolation. But it was the SCCM's statement after the event saying she'd do the same again that suggests she is doing the wrong job. So I'll stick with my "churlish" remarks.
And I'll pose another question to those who think the SCCM did the right thing. Would it have been acceptable for any of the other cabin crew or even a passenger to have initiated the evacuation? If not, why not? So why didn't they?
For what it is worth, recycling fans small horrible when they fail. I have had several fail in flight and the acrid, pungent, electrical burning smell takes ages to dissipate. Similar to smoke, the odour appears to get into fabric and soft furnishings and stay for ages. The smell lingers long after the source expires. Returning to this incident, I can understand the cabin crews' distress because to them it would appear that either no action has been taken or what has been done was ineffective. Unfortunately, this is one of those occasions where over-reaction has caused unnecessary injuries.