The Queen often feels Eileen is far too critical but the latter feels it is better to ask awkward questions and walk away from something/someone dodgy (or dodgy as it seems to her) than be caught out and have regrets later. In her line of work, mistakes can so often have fatal consequences. And Eileen takes the attitude that is not for her.
Eileen considers one of her successes to be that she has persuaded Hanastrew to take the same line.
Eileen also feels because it is well known in the Kingdom she cannot be bribed or threatened, that is an asset to her. Certainly it encourages the people to trust her. For Eileen, that is priceless.