I want to take 1 or 2 more electives but my F-1 has already expired and the department refused to extend my I-20. A friend offered me a help to enlist me as an intern at his workplace while I spend the whole day studying. I am afraid that the immigration office checks me at the workplace and found out I am not here. Will they actually check my attendance at the workplace? Is there any case of due diligence or investigation?