2019 Chevy Traverse Wont Start

Before you start throwing money and parts at this, did you plug in a memory saver device before you disconnected the old battery? If not, you probably need to be towed to your local Chevrolet Dealer to have the computer flashed. In many newer vehicles the computers must have power at all times, including during a battery replacement. If not, they need to be flashed (reprogrammed) by the Dealer. Hope that helps! Jim

I had the issue before I changed the battery and starter thinking it was reason it wouldn't start

Ok, in a way that's good. Does the engine crank over? If not, try starting it in neutral. It could be the neutral safety switch? Any security lights on or flashing? If so, the computer isn't recognizing the key. Again, if this is a no crank situation. Jim