Hi Ricky
Your experience is identical to mine
I would suggest that you repeat the battery draining as before for as many times as you have to to get the cover working (you don't need to let it fully recharge each time, once you've tested it and not worked you can unplug the charger and run it back down). It will work eventually as you have already proven.
Then whilst it is working, before you turn it off, update the firmware again. I also updated all the drivers. This worked for me
I had an interesting experience with mine. The retailer, JBHIFI has an extended warranty policy that covers goods even without buying the official extended warranty with the product. It was suggested I take the Surface back and see if they would cover the repair/replacement. Unfortunately their policy took it to two years for computers and my Surface is three years old. However, they said they would send it for an assessment and cover any costs involved in getting a quote, which can be anything up to $100 from the repairer.
A month later they told me the repairer quoted $765 for which they would replace the Surface. My guess was that they were going to send it to Microsoft for a refurb replacement. I declined that and asked them to return it to me. I can get a refurb myself for $650 from MS.
When I got it home I made sure the battery was exhausted, attacked the Typecover and turned it on. The Typecover lit up and worked!! There was a month of updates to install with firmware updates among them. I thought that with all the new updates it would be OK.
However, restarting the Surface through the update process caused the Typecover to get lost again. I've run the battery down a few times, plugged in the charger, turned it on, no backlights. Run down the battery, etc ... So far, nothing.
I'm stuck with the bluetooth keyboard for a while yet, but seeing the Typecover light up that one time gives me a bit of hope for the future.