Recently, my business college opened an office; his office requires cleaning. He hired a cleaning company, but they did an illegal activity while working. Is reporting against them a good option?

Yes! You can. Getting commercial and residential services in terms of need is a good choice. Before handing over the task to both, ensure that both services vary on different requirements. However, having gotten the services, you can contact the company if you find any illegal activity or bed services.
Additionally, if the illegal activity ruining your name or defaming your personality, you can take strong action against the services.
And, if you have gotten bed services in the name of good services, you can still contact the department.