if pilot or co-pilot states displeasure with mechanical condition of a commercial airliner, can/will the administrators over ride and insist that the flight be flown as is? I don't think it happens like that in N. America but what about elsewhere?
Of course they "can". Whether they will or not is an entirely different matter.
I have personal experience of a small UK scheduled airline that operated for years with no action taken despite numerous reports (some detailed to the nth degree) to the CAA of their appalling maintenance (or rather lack of it), quite apart from the heinous operational offences they committed on a regular basis. Years after I left I was still hearing the same stories from younger colleagues who had worked for them recently. Anyone who flew for that ghastly outfit will name it instantly.
Nothing was done.