Absolutely no harm in trying.
It will not cancel your original app.
I didn't know your dates ... 440 days is ridiculous for EAD/AP ... I assumed you are on your 2nd EAD/AP -didn't even think that your original EAD/AP is taking this long !!
You should probably do more than just walk to the local office -- did you try contacting senator/congressman -- I mean there is a lot of hardship for you (if you don't have a non-immgrant visa stamp, then travel is imparied w/o AP)......
I have started an inquiry using a congressman. Let's see how that goes
your wait is way more than reasonable ... so your RFE reply contained all the docs reqd for ability to pay - correct ? And you also sent in the Educational evaluation (required if your degree was not from a US school) - right ?
For Ability to pay they specifically asked companies 2002 tax statements and for degree they asked for degree certificate. So we just sent those, I argued with my lawyer to send more, but his reply was to just send whatever USCIS asks for.
I wish you luck - you need it.