Her name appears on the NWU 2003 Commencement program with a Bachelor of Science in Communication from the School of Communication, formerly the School of Speech. It is in a long list of names and you will see the degree if you scroll up slowly, though the formatting is wonky. .
It appears she did not do any double major but a vanilla Communications degree.
US Treasury Secretary Paul O’Neill visited Argentina in August 2002 right around her 21st birthday which explains why some articles say 20 and some say 21.
I don’t know if NWU has fall and spring commencement but she likely missed fall commencement deadlines and/or needed a couple more credits and so went for spring commencement even if she had already started auditioning.
https://archive.org/stream/annualcommenceme2003nort/annualcommenceme2003nort_djvu.txt
ps: several articles stated the internship was 6 weeks not 6 months, which makes more sense.
Thank you for finding that commencement program! I knew I’d seen it around but I couldn’t .
I’d also add that most–if not all–universities and colleges in the US, require you to apply for graduation. You have to prove to the registrar that you have met the requirements for graduation. You do not inadvertently end up on the commencement program by accident.