***Topic locked for further comments. OP has been given good advice. OP should remember that a person cannot enter the US via a B2 visa with the intent to stay and adjust status. Any further discussion of that borders on violation of the Terms of Service. That topic is not to be restarted. OP's friend is free to join Visa Journey and discuss any other subject***
- VJ Moderation
The ability to financially qualify for sponsorship will be based on his proof of non-taxable income which he will have to provide as supporting documentation....not what is entered in boxes 24 a-c on the I-864. Like I said, a formal letter is fine as an explanation of taxes not filed also.
I would write "N/A" Then, indicate the reason beside the boxes. If you were not required to file for those years, you can write "Reportable Income below reporting threshold" beside the boxes if that was the reason.