Nonlinearities in Fully Differential Op Amp
Your opamp is not rail to rail, the datasheet says:

Common-mode input range 1-4V typical 25°C, 1.6-3.4V worst case for 5V supply.

You must make sure your resistors set the DC operating points to the proper voltages.

Also the output is not rail to rail either. Check "Differential output voltage swing".

"Differential output voltage swing RL = 1 kΩ, Referenced to 2.5 V ±3.3 ±2.8 ±2.6 ±2.6 V Min"

Taking "±2.6 V Min" this means the outputs will swing to 1.3V away from 2.5V, that is from 1.2V to 3.7V.

You require a 1Vpp differential signal, so the non rail-to-rail output would not be a problem, except you set VOCM to 1.5V, which makes me think the next thing in the signal path is a 3V3 ADC, so even if it works in simulation, I'd be very cautious of using this opamp...