This is sort of OK, except the capacitor connects across the (+) terminals of the two input opamps, and does not connect to ground.
Also, we don't care about the CMRR at 64 kHz. We care about it at up to 10 kHz, but not above. The sample frequency of the ADC is 64 kHz, but all of the models run at 16 kHz or less, so the Nyquist frequency is 8 kHz.
And doesn't the value depend on the resistors?