A SINGLE MEL item may warrant only 'normal' scrutiny, but ANY combination of multiple deferred maintenance items warrants close scrutiny by the Captain and his best judgement as to take the airplane or not. The Captain didn'n need an "excuse" -- he believed the airplane was not safe FOR THAT FLIGHT, IN THAT CONDITION
But the "Captain's Judgement" is the very thing that apparently fails with this outfit. They either have insufficient experience to be making multiple MEL calls, or they are basically indentured servants until they pay off the training debt, or they are overridden by a cavalier management culture which they are too vulnerable or exposed to challenge effectively. Or maybe it's all of the above.
Choices are be a Captain and hope it doesn't kill you, or be a (unemployed) hero and call it like it is. A culture of ethical and morally correct behavior can only exist if the entire organization subscribes to it. It's no good if only the flight crews understand that point if management will neither support or endorse appropriate command behavior.