I need Help to interprete X431 diagnostic report on LX 570 on 2009 Lexus LX570

The car was jerking and not firing right. I have also recently changed fron brake pads. Called my mechanic that has diagostic Machine to read, but not sure about his interpretation. So Ineed other opinions before I let him undr my hood
Error Code PO 300- Random/Multiple Misfire detected;
Error Code CO 210 Right Rear speed Sensor: C!241 Low or High Power supply voltage; Error Code C2122 Transmitter ID2 not received (main)
What do these mean and how can I fix them.
Thank You

Asked by for the 2009 Lexus LX570