All of the past warmings did seem to have "involved" the CO2 boost, however - they just appear to have started without it, and likely contributed to it in a feedback cycle.
CO2 boosting is going to trap heat and cause warming - that's just physics. How the CO2 got into the air in the first place doesn't change that.
The apparent possibility that warming itself in some way boosted atmospheric CO2, in the past, is a warning to us - there's a possibility of a positive feedback loop which will amplify our fossil fuel CO2 boost via the warming it causes, and amplify the damage while making remediation even more difficult.