Screen flashing/battery not charging

My phone got wet. It was fine and I immediately shut it off and it shutdown as normal and I dried it out. Go to cut it back on and when the battery had power it would show the charger connector symbol when it was connected and it would only boot to the OS install mode. But if connected to the charger the phone will stay on and the battery will die while connected. So I replaced all the ribbons and the battery and the ear piece section of the phone and samething. When the battery had power it would pull up the charging screen and only the Install OS mode but then it died again. I’m thinking maybe the rom was wiped somehow during shutdown causing a problem with the battery not charging. while connected. while at the same time the screen consistently flashes on and off when connected to the charger and the battery is dead. You can also feel the current vibrating while holding it when it’s plugged up. But since the digitizer is fine and it loads the OS install screen and shows the battery charger connected then the motherboard should be fine right? So if I can fix the battery situation and reinstall the rim it could fix it. I have all the soldering equipment and the know how to use it. So please tell me what I need to do. Thanks