Hi @SonOfOdin know you are saying there is no moisture, however has your mate's phone actually been cleaned? If charging with device switched off does not work try clearing the cache partition, sometimes this can fix charging issues.
Follow these steps:
1. Turn off the device.
2. Press and hold the Volume Up key and then press and hold the Power key . Should not need to connect to computer in A series.
3. When the Android logo displays, release all three keys.
4. An 'Installing system update' message will show for 30 - 60 seconds before the Android system recovery menu options appear.
5. Press the Volume down key several times to highlight wipe cache partition.
6. Press Power key to select.
7. Press the Volume down key to highlight yes, them and press the Power key to select.
8. When the wipe cache partition is complete, Reboot system now is highlighted.
9. Press the Power key to restart the device.
obviously may need to take to Service Centre mind you.
Sime general charging advice here. https://www.samsung.com/uk/support/mobile-devices/what-to-do-if-your-phone-is-not-charging/
I do not work for Samsung or make Samsung Products but provide independent advice and valuable contributions.
My Device- S21 Ultra 5G ( SM-998B/DS ) CSC= BTU , 12GB/256GB
One Ui 5.0,Android 13 .