"I attempted to e-file today"
You cannot e-file yet. E-filing has not opened. The IRS will not begin to accept e-files until the end of January. If TurboTax opens e-filing sooner, all that will happen with your return is that it will go to sit on a server for a few weeks until the IRS opens.
And.....WA has no state income tax, so there is no state return to prepare or e-file from TurboTax. If WA has a new form for "Working Families...." then you have to sort that out and file it on the state's site or mail it to them. The inability to do that using TurboTax does not prevent you from e-filing your federal tax return. But you do need to wait for e-filing to open in order to e-file anything.
https://workingfamiliescredit.wa.gov/
As mentioned in the post, the issue is now resolved. However, it is important to know that TurboTax does have a new Washington product for those customers who are eligible for the Working Families Tax Credit. This new product allows those customers to file their request for the Washington State Working Family Credit alongside their federal return in TurboTax.