My guess is OP tried to plug the phone in before it was dry and fried the SSD (or whatever apple uses for their storage) or something on the board having to do with storage. But if not, I’ve pulled devices out of recovery and DFU modes using iMazing quite a few times. You get familiar with doing it when jailbreaking checkm8 devices (iPhone X, 6s, iPad Pro 10.5”).
I’m guessing what happened is they charged it before it was dry. Even if it didn’t get inside the phone, and was only in the lightning port, it could have fried something. Best guess anyways.