Electret microphone - connect to Codec
Data sheet circuit for microphone: -



From this you can somewhat conclude that the microphone might need a minimum DC current of about 3 volts / 680 ohms = 4.4 mA. This means that using 2 x 10 kohm to feed DC to the microphone is likely to be insufficient.

I would configure the MAX9860 for single ended inputs to match the circuit shown in the microphone data sheet.