The client did not give me a W-4. We are preparing her 2018 return now and she only gave me an IRS Wage and Income Transcript. As you probably know, the IRS no longer provides the entire EIN on the Wage and Income Transcript, however, the last 4 digits that they do provide match the last 4 of the EIN I found on our state business registration site. 

My client did not work for this company in 2019 so I don't have that as an option either,