Is working as a security guard at a fine arts college that produces statues and images of animate beings, some of which are nude and immodest, permissible or forbidden, especially given the employee's distress and discomfort, and the rejection of his transfer request?

If the college is not entirely dedicated to unlawful activities, but rather includes permissible sections, then it is not possible to definitively rule that working as a guard there is forbidden. It is advisable to seek another job that is far from objectionable matters, and until he finds one, he must lower his gaze and condemn the wrong, even if only in his heart.