No signs of life, draws power from wireless charger but not wired

My friend's iPhone 12 shows no signs of life (nothing on screen, no charging noises/vibration, etc.) I don't have a USB power meter but I have a kill-a-watt style meter. Using that with an Apple 5w charging brick shows the phone sometimes drawing about half a watt for a second at a time, but ultimately not drawing any power. (I cleaned the charging port and nothing changed.) With a wireless charger, the meter shows about 6 watts and the light on the wireless charger is on, signaling that a device is charging. I left it on the wireless charger for about half an hour and it kept drawing power, and got hot (I don't know if it would normally get as hot as it did, I don't use wireless charging for my devices) but still didn't power on.

I opened the phone and tried to measure the battery voltage with a multimeter, but got 0v. However, I couldn't find a pinout online so I might not have been measuring it on the right contacts, but I tried all the contacts I could.

I was thinking it might be a battery issue before I tested with the wireless charger but now I fell like it could be something else. I don't have much experience troubleshooting this kind of issue, so any advice will be much appreciated.