FDC2214: Optimal components for resolution and low ambient drift

Tool/software:

I'm trying to find the optimal components for using with FDC2214 in the sub-femto-farad range. Namely, the LC tank and reference oscillator.
From what I understand, a critical factor for the LC tank is the temperature coefficient of the capacitor and inductor.
I'm having a bit of hard time finding inductors that specify the ppm temperature coefficient . Also, is the Q factor relevant?

- We tried the EVM and the resolution and drift (ambient temperature change) obtained was not enough for our application.

FDC2214EVM
Samsung CL10C330FB8NNNC 33 pF +/- 1% C0G/NP0 0603 (±30PPM/°C)
CMH322522-180KL Inductor, Shielded, Ferrite, 18 µH, N/A ppm/°C
CTS Electrocomponents 625L3C040M00000 40MHz +/- 20ppm, < 1 ps jitter

- In SNOA940A it is mentioned that "using a PCB coil, the 1σ resolution of the FDC221y can be as low as 0.08fF" (using cap and coil from LDC1612EVM)

SNOA940A/LDC1612EVM
PCB coil [18.5uH] + 20 pF PCB parasitic capacitance (source: https://e2e.ti.com/support/sensors-group/sensors/f/sensors-forum/533215/pcb-coil-for-fdc2214-in-snoa940-document )
CTS Electrocomponents 625L3C040M00000 40MHz +/- 20ppm, < 1 ps jitter

Any suggestions as to what commercially available components would yield the best and most stable results for the FDC2214?

Using the FDC1004 is not an option for us as we need at least 500 sps sampling rate. 

Thanks!

~Natan