However, I do not need this feature, since I have a DC supply of 12V that I can use.
No PWM controllers exist without the HV module with anything like the spec I require.
Do you think it will be OK to just leave th HV pin disconnected?
In some designs the HV pin may just be a resistor limited,
shunt regulator that feeds VCC internally. In that case you could
just feed VCC and leave HV open.
But I expect your answer lies with the mfr's datasheet and app
notes, not generalities.