Wait would this give us the unredacted PDFs?

That's the idea yeah. There are other people actively working on this. You can follow vx-underground on twitter. They're tracking it.

I think it's the PDF files that were attached to the emails, since they're base64 encoded.

From the unredacted attachments you could figure out what the redacted content most likely contains. Just like the other sloppy redactions that sometimes hide one party of the conversation, sometimes the other, so you can easily figure out the both sides.