U.S. Tax return – self-employed – print out and attach J/USA6?

I've filed my own tax return for the past few years (expatfile) and I've had no problem telling them that, as a freelancer/self-employed person, I pay into Japanese nenkin (which I do) and therefore don't owe payroll tax. I recently contacted a new tax preparer to see if he could take over my tax filing duties (other things are getting more complicated and I don't want to do it myself), and he said that if I'm a freelancer, I can't file online and have to print out my tax return and mail it in together with J/USA6 (proof I pay nenkin). Anyone working freelance and filing taxes in the USA actually doing this? It seems like it will add a bit of expense to my tax bill. Do you think I can find a tax preparer willing to go with expatfile and do the whole thing online? Was expatfile cutting corners? Thanks!