Well, the interface for the HX711 is not I2C, so you can stop messing with that.
It is a unique custom serial interface.
Most likely solution is to bit bang the interface using several GPIO pins.
You should bring it up in layers.
Start by learning to read the raw value from the part at a low level, before you start trying to process the results.
Write some diagnostic code, so you can dump the bits as they come in.
Get an oscilloscope, so you can watch the bits wiggle and read them on the scope.
--- Graham
==