Lightning pinout

You can probably find a schematic somewhere online, but seriously I recommend against the self-fix. You hook something up wrong and a power surge destroys your iPad you are stuck with a broken device that apple will very well not replace even out of warranty, and even if they do it'll be hundreds of dollars.

The $20 or less a cord will cost you is well worth having something that'll work vs a gamble every time you plug it in.

Other than buy a new one?

Given that it charges your device and the risk involved with DIY and that same DIY potentially voiding your warranty if you do it wrong, I'd suggest that you just buy a new cord.

Push and pull the plug and not the cable.

Apple won't say unless you sign a licensing agreement. And we don't know.

Methinks you're gonna have to bite the bullet and pony up the cash.