How should one act concerning the wife's discomfort with the mother and brother entering the bedroom to clean it or watch television, especially since the husband sees no objection to that?

If your brother is not a mahram to your wife through fosterage, then he is a stranger to her, and it is unlawful for him to look at her or be in seclusion with her. His entry into her room is not justified, even if it is to watch television. As for your wife being bothered by your mother entering your bedroom, she should not be, unless there is a reason, and she must respect and honor your mother.