I still don't understand how anything these students did was wrong, and how anything ICE did was not fraud. My understanding from back when this first came out

I still don't understand how anything these students did was wrong, and how anything ICE did was not fraud. My understanding from back when this first came out was: 1. ICE created a "university" and made it as real appearing as possible 2. ICE advertised their university to non-americans 3. ICE's university told the applicants how to apply for student visas 4. The students came to what they were - by design - led to believe was a real, accredited, and good university 5. ICE arrested the students for immigration fraud and stole their tuition money I do not understand on how (5) did not violate 4th amendment on multiple grounds, and I'm not sure how this would not be simple entrapment even if there was some belief/knowledge the school was not 100% above board.