Surely, it is as simple as that isn't it John.
Climate drives Co2 levels - not the other way round.
Not exactly: Milankovitch Cycles drove the warming & cooling, and the CO2 released e.g. from permafrost decay in transitions from glacials to interglacials amplified the warming. So you have tipping-points relative to Earth's orbital cycles and CO2 acting as an alternatively negative or positive feedback. Did I not say ages ago that it is the thermostat of the planet?
Cheers - John