Dead iPad after new screen replacement

Unless you work in a high-static environment, I wouldn’t consider that as a problem. Sometimes forgetting to isolate the battery (or doing it improperly) can cause issues with the backlight circuit but even in those instances, the device will still boot and be recognized by iTunes.

So double check your work and take a close look at the connectors, flexes, and the surrounding areas on the logic board and look for debris or damage. I would also try to connect the original screen if it still worked (just cracked) to try and rule out the replacement screen as an issue.

If the issue is not screen related, there isn’t much more you can do from a DIY perspective.