PowerShot G7 X Mark III wont turn on

[hutchqt]

i have bought a g7x iii for hefty discount used but i cant seem to get it to turn on and nothing i read online seems to help 

it has a aftermarket battery it did not come with a charger so i ordered one off amazon when i first got it i tried to plug it in with a usb and i got a little light indicator but now after charging the battery it does not show up anymore and it still won't turn on 

i think the battery is fine I checked it with a voltage meteor and it reads fine is it just a battery problem or is it just cooked 

for a recap i get no lights on it pluged  it with or without a battery or just on battery it does not look courted and the battery reads fine on a voltage meator is there anything im missing or is my camera just dead

[FelixKH]

Why not buy an original battery for it to test out? Was it working when you bought it?  

[Tronhard]

Without wishing to rub salt into a wound, it sounds like this camera was discounted for a reason.  Was it sold new or used, and does it come with a warranty that you can activate?
As Felix said, it makes not sense to replace one dubious battery with one that is not known good - you have no idea if that 3rd-party battery works.
Honestly, if you can return the camera I would suggest you do so. I would not be surprised if this is a grey market or used (or damaged and repaired) camera and Canon may not support it if it was altered by a third party.