As an update in case this helps anyone else, I went back through into AskEmma, got an agent on live chat, and created a new request. But! This time, I specifically mentioned that I have new evidence I need to provide (that wasn't part of the I-130 application obviously), so please note that, as well as the reasons for requesting the expedite (last time, the agent just asked, what would my reason for expedite be, and I only gave a very, very high level reason, I guess its better to include some detail at the request stage..)
I guess that worked, because today I just got back an email from the Vermont SC to provide the additional evidence by fax, so will be working on the info package over the weekend to send next week.