Mashgiach for Kashrus woman

Igros Moshe (Y.D. II #44):Question Concerning the widow of a talmid chachom who had a position as masghiach of kashrus and with his death she is destitute and has no way of providing for herself or her children. She is a modest woman and truly G-d fearing as well as being smart, understanding and responsible. She can relied upon and in fact was working under her husband’s supervision and that was her parnossa until he died. You want to know my view as to whether she can now serve i as a mashgiach? Answer From the aspect of believability, a women is fully believed concerning prohibitions. The basic law is that a single witness is believed for prohibitions. However some sources indicate that women are only believed for Rabbinic prohibitions. Tosfos explains that tasks which require great effort or matters she can’t control she is not believed. But that is only for matters which are presumed prohibited. Therefore supervising kashrus means she prevents people from eating that which is prohibited from food which is not presumed to be forbidden she is to be believed even if the food is not in her control. It has been standard practice in every generation to hire women to cook and buy meat and other foods and rely on them that it is kosher. . In conclusuion from the aspect of believability there is no problem that this women can serve as mashgiach since she is established as good woman with solid knowledge and understanding as the job requires. Howver there is a problem from a different aspect.  The Rambam states clearly that all positions of authority in Judaism can only be males. I don’t know the source for the Rambam’s ruling. The Sifrei that is cited by the Kesef Mishna and others  only states that the ruler must be a male king and not a female queen but no mention is made that all positions of authority must be male. It must be that the Rambam decided that on his own. . It is reasonable to say that a kashrus supervisor is considered a position of authority as Rashi notes that a supervisor over weights and measures is considered an appointment of authority since both positions require opposition to deviations from standards. Consequently the Rambam would prohibit a woman being appointed as mashgiach. . However it seems to me that not everyone agrees with the Rambam. The Chinuch and Tosfos seem to disagree  as do Rashi and the Ran  Thus it is not clear what the halachic status of the Rambam’s view is. Consequently in the case of great need such as the livelihood of this widow and her children one can rely on those that disagree with the Rambam and appoint her as mashgiach to replace her husband. However there is a way to appoint her which doesn’t conflict with the Rambam.  If she is officially hired by a rabbi  and is thus while she is not the official boss but she does the actual work and therefore she has no actual authority which is totally given to her boss.