Son received a W-2 and a 1099-NEC (expense reimbursement) from Internship

My son had a summer internship for which he was a W-2 employee.  He also received a 1099-NEC for a flat payment he received from the employer which was supposed to reflect a reimbursement for housing/travel expenses that was incurred for the summer.  He didn't submit any documentation to the company reflecting these expenses.  Is he required to file a Schedule C?  Can he deduct expenses incurred, such as rent paid for the summer and/or milage traveling to the job?  

 

Thank you.