You can easily bypass the mic pres on the iD44 MKII by simply patching the output of your other mic preamps or gear into the insert return on input channels 1 or 2, which is a very pure differential line stage into the ADC, therefore completely bypassing the onboard mic pres and line input stage.
This would allow you to still use the excellent Audient mic preamps from inputs 1 and 2 for other duties in the analogue domain (output available at the insert send jack).