Hi all,

I know this is going to be a long shot, but I hope someone can give me some pointers.

So long story short, last week I accidentally plugged the battery incorrectly (spare battery with 2 pin JST connector).
I plugged it off right away because I saw I took the spare nimh batter that doesnt have the 3pin connector.
And then I plugged it back with my main battery and viola, nothing turns on.
Tried to take off the case to have a look at the board, but I can't see anything odd, can't see or smell any burnt chip as well.

Does anyone have any idea for me to look? I have multimeter but I have limited knowledge of electrical components.
Below is the picture i took, I dont want to overload the server therefore i uploaded to image hosting instead.
https://imgur.com/Ph87BK8
https://imgur.com/UHNsgqD
https://imgur.com/pciivrQ
https://imgur.com/8BRk4zE
https://imgur.com/TvUHdNa
https://imgur.com/94qNxvF
https://imgur.com/5ZUG6vC
https://imgur.com/6COrcDC
https://imgur.com/0h4euvg
https://imgur.com/OQSFuSe

Any help will be appreciated, thank you in advance!