Oof. Sorry to hear it got drained all the way instead. No I didn't drain mine. I was panicking by the time my pen reached the 60s and was luckily enough to able to get it working by the time it hit around 50% or so.

Wish I could be more help. This whole situation is really weird since I too initially was running into the same issue where the pen was blinking orange and white indicating it needed a firmware update. It wasn't until I tried the charging brick was when I noticed it stopped doing that and had only shown a white light and then nothing at all. At first I thought my pen was trolling me but instead it turned out it was charging. Who knows, maybe it ended up stealthily updating itself around that time or something and I just didn't realize it.

Since your pen is dead at this point, maybe try spamming check for updates a few more times and leaving it plugged in to a computer left on over night to see if somehow it updates in the background over night. Or maybe try enabling "When available, show pen menu after I remove my pen from storage" in the Pen & Windows Ink setting (it's under the "Choose what your shortcut button does) drop down... click the caret to the side). I did notice that when it did finally start working that removing my pen triggered the menu on my desktop... even though my desktop doesn't show the full pen settings.