The employer should have issued a total new W-2C (corrected) to totally replace the original but some employers only send the boxes that changed and expect you to update only those boxes. Check with your employer.
He said he will escalate it up the chain and see if he can find a definitive answer about it. In the meantime, my taxes are due so I'll delete the thing so I can efile.
You may be better off just deleting the W2.
-Is the $0 due to nontaxable code J in Box 12? (Nontaxable sick pay)?
-Are the state wages (Box 16) also blank or zero?
-Are your total Social Security wages for the year (W2s, Box 3) under $118,500?
If you answered Yes to all 3 questions, delete this w2.
If you answered No to one of them, put $1 in Box 1 so you can efile.