The audit might be done by IRS, or the audit could happen as part of a university audit of eligibility for Pell Grant funds. Well over half of these recipients were audited every year ~ taking up more than 30% of total IRS audit resources.
The other trillions of dollars in federal tax payments were subject to cursory evaluation.
You were just unlucky!
I didn’t apply for any grants, and I have never claimed any earned income tax credit.
I was never given any reason for the audit. They went back 5 years. It all started when I started sending money to republicans and writing letters to ‘rats.