i have have the "exact" same beahvior. switch looks like it charges but actually it discharges. with the orig charger i get the charging symbol. everyother charger doesnt give me the carging symbil- i also replaced bq, pi and mt ics. also replaced the usb port.
5v. pin 1 has 15.
the esd device wasnt isntalled on this board.
https://ibb.co/4jZR1dX
ignore the blackness on the caps. its just paint.
would be nice if you are still active and have an ideAS: