No have idea that pins the same or not, by the way 'll check it information about it in the internet. but i know that mainboard microchips (condensators or something like this) are different which are controlling incoming chargs via usb-to-usb and usb-wallcharging. So, must check it with electronicer master whether is the usb-wallcharging controller working or not.

but the first, i think you must check software side, then check hardware. just backup your all data, then flash it (firmware&emmc all together), with zeroes flashing
zeroes flashing of firmware
then flash emmc
check this for mor information and guide to flashing options
by the way, if you will have cmt error during flashing, then find your old firmware, do the operations up there, then flash only cmt.

PS: DO NOT FORGET TO CHARG DEVICE FULLY. in your situation via noutbook\desktop.

check after this, whether does wallcharging works or not? and here are steps what you have to do.
1)detach all connections from Nokia N9 (usb,headphones ...)
2)if you dont have find the wallcharging controller,with which one you can switch off electric coming. if you have thats nice, so switch of electric from wall.
3)plug in your wallcharger to the wallcharging place (but not switch on yet)
4) plug in other side of your wallcharger to your N9
5)swtich on the wallcharging electric and see what happenning and let here to know.

Do these steps with your N9 when the device is working and when is powered off, try two variants.

PS: sorry for bad english