What is the ruling on working in companies that differ in their nature of work and in gender mixing, especially since one of them is contributed to by the "National Office for the Wine Trade," in order to choose the least harmful option for earning halal money?

It is permissible to work in a fish farming company, even if some shareholders' money is mixed (with impermissible earnings), and in a company that builds factories and public utilities, while refraining from working in explicitly forbidden places such as nightclubs or bars. There is no harm in working in something that may be used for both permissible and impermissible purposes.