It looks like the INA300 IC starts-up in transparent mode.
Is there a way that you can start-up in Latch mode?
CH1 - Output current
CH2 - Alert signal
CH3 - Enable signal
CH4 - Latch signal
A) U10 starts-up in transparent mode even when forcing LATCH pin high with external power supply
B) MCU boots up and toggles enable line
C) Over current event occurs and latches alert low turning off U9