Yes. She can use her self selected PIN instead of her adjusted gross income. She would have chosen the PIN when filing her tax return last year.
If your friend doesn't have access to last year's tax return to see her adjusted gross income, she can request last year's tax
transcript from IRS.gov.
The tax transcript will show the AGI (adjusted gross income).
When requesting the transcript from IRS.gov you
need to choose the tax
return transcript type when making your
request. Click
here for a link to IRS.gov's get
transcript page.