If it was bumped to the point to crack the digitizer the hit might as well have shorted something inside, either a connector, button cable or a component on the logic board. The fact it feels warm doesn’t necessarily mean it’s charging, shorts allow current to flow where it shouldn’t and create heat. I would avoid keeping it charging since that apparently doesn’t work. If you feel like getting in a DIY project, you could try open it and check all connecting parts to the logic board are firmly in place and there are no signs of burnt anywhere. Besides that, we get into logic board troubleshooting and that requires knowledge and tools. Here you can find all replacement guides you can use as a reference if you decide to try yourself, but I’d warn you iPads repair is not a stroll.
[[Topic:iPad Mini 2 Wi-Fi]]