Self employed

If she is being claimed on your return as a dependent, she may have a modified standard deduction and with self-employment, there are no taxes withheld, so it will look like more tax due than a job with a Form W-2 which has withholding every pay check. 

Is this the screen you meant?

It sounds as if she does the referee work regularly, so it would not apply to this case. If she was a contestant on Jeopardy and won $10,000, that would not be a regular activity and would not be taxed as self-employment income. 

She may have additional expenses for this self-employment, such as mileage to games, whistles, uniforms, or other supplies required for her to do this work. She may qualify to deduct those expenses against her self-employment income. 

To enter the income that was not on a Form 1099-NEC, in the Schedule C section with Expenses and Income, click on Add income for this work. 

And check Other Self-employed income, includes cash and checks. You can enter the payments from the two organizations that did not provide Forms 1099-NEC