Thanks for checking, this would have been interesting. That said, as the eSteuerauszug is used as alternative to a regular broker statement, it’s used as documentation/evidence from the broker (especially important when declaring withholding taxes), so I suspect that even if that tool was available to anyone, they wouldn’t accept unofficial PDFs.
An interesting compromise would be for tax software to allow importing the (unofficial) XML file while still attaching a regular broker statement as proof. I don’t expect that to happen, though, it’s presumably too niche.