Happily, I haven’t seen a UN statement in 4-5 years.
my recollection is the instructions say report income on line 1 as wages (if you can make the software do it… at the time we could not). Ended up reporting on sch c with SE. The Employee was able to file with UN to get reimbursed for SE tax and did. 

No idea if this is still applicable. UN is PITA.  
2 other useless notes… while no W2 or 1099, the UN does report the income to IRS…The UN tax help was nonexistent 

Good luck… hopefully someone else here can help