What is the ruling on warning against dissolute women who frequent the café, and what is the ruling on the money earned from the café, given that no forbidden items are sold therein, and one is unable to expel them because they threaten to file a complaint?

Protecting the honor of Muslims and safeguarding their dignity is a religious imperative. Islam forbids the spread of indecency among believers. If the women in question are not openly engaging in immoral acts or known for them, then attributing such acts to them is considered unlawful slander. However, warning against them due to their immodest display (tabarruj) and mixing (ikhtilat) is an obligation, as it falls under the category of enjoining good and forbidding evil. Money earned from a coffee shop is lawful as long as no forbidden items are sold or forbidden activities conducted within it. You must be careful to lower your gaze and enjoin it upon others when those you described as immoral women are present, if you are unable to expel them.