Yes. You dependent should file a return because his Unearned income is over $350 AND gross income of more than $1100
Edited [03/26/2020, (10:33 AM PST)]
The earned income of $2,200 is part of the gross income. Since he meets the criteria of having both more than $350 in unearned income and total gross income, which includes the earned income, of more than $1,100, a return is required to be filed.
Try this link, where he should be able to file the return for free: FreeFile delivered by Intuit TurboTax.
Your minor is not a single status filer. Your minor is filing as being claimed by another. Huge difference there. Please visit the IRS and take a short, anonymous, online quiz to verify your questions and answers. Scroll to the bottom and click Begin at Do I Need to File a Tax Return? For a full list of quizzes available, see IRS ITA.