Not a good idea to jump aboard an old thread like you did. I think the answer could be found above, but here is my short summary.

1. Nothing you do with TurboTax applies to what you would do here.

2. You need a client and a preparer signature and dates on the 8879.  You do that by one of two ways. Wet signature from the taxpayer(s) or e-signature from DocuSign (or whatever other service you might find) when you can't get the wet signature.