Modelling differential amplifier input circuit
If you look at the schematic, the input is differential, this means there are actually two inputs w.r.t. ground, in antiphase (as is the case here). The same for the output, because if you look at its datasheet, the FB pins are the same as OUT.

Soo you have a simple LC lowpass, followed by a differential active filter, which is a simple 2nd order bandpass. The LC filter is not loaded with any resistor, so you would expect the whole result to be an undamped (to a degree) lowpass combined with a 20dB/dec bandpass.

It looks like what you plotted is similar, but the way you have drawn the equivalent schematic does not reflect the whole truth. Here is an attempt with LTspice. I didn't use the model for 4940, but I used another differential opamp, only for the show:



To the right is the same version, but single ended, and the result is the samem save the amplification due to the bandpass being an active filter, as opposed to a passive one.