Should a paid intern file as resident if they are from another state?

[ATF32]

I was a paid intern, who temporarily Worked and lived in Georgia for 5 months (as student my primary residence is NH).  How do I address residence for filing my GA State tax return?

[SherylSTaxExpert · Accepted solution]

The State of Georgia says that you must file as a non-resident if Individuals must file if: 

1. You are required to file a federal income tax return, and 

2.  You work in Georgia or have Georgia-source income

However, there is an exception

 Legal residents of other states are not required to file if their only activity in Georgia is working for an employer as an employee where wages for such services do not exceed the lesser of 5% of income from all sources, or $5,000. If this is not the case you would have to file as a non-resident.

[Victor21]

Have similar situation for my student. He is resident of WA (no income tax) and a full time student in GA. He did internship for a WA company (but worked from home). His W2 has GA as a state in box 15 even though no state taxes were withheld. This is probably because paperwork had his GA school address. Does he need to file GA because of box 15 notation as a non-resident? OR can he clarify to GA somehow that this was in error and no taxes are due to GA?  
His income was more that $5000 (so the above exception probably doesn't apply).