I have three questions for you.
1. Why is the average temperature of the Moon less than that of Earth, even though they are about the same distance from the sun?
2. Why is Venus hotter than Mercury even though Mercury is closer to the sun?
FWIW, a massive slew of factors (too many to list) determine the average temperature of a planet, and GHGes are just one of those many factors (albeit an important one). Unfortunately, the Stefan-Boltzmann law of thermal radiation is often mis-applied to "average surface temperature", which in fact is not predictable via that specific equation. Thermal capacity, photochemistry, rotation rate, and emissivity are all involved in maintaining the "average" temperature.
3. Off the top of your head, in your opinion, what are the three most important equations in thermodynamics that say that it is possible to add CO2 into a closed system receiving solar energy without causing warming?
Another misconception is that CO^2 "adds" energy to the system via "backradiation". That's not at all how it works (much more complex issue involving collisional line broadening/time delays between the emission/diffusion ratios with altitude, which raises the aggregate emission height).
In fact, the presence of CO^2 actually reduces the thermal capacity of the atmosphere itself because
it emits in the infrared spectrum (the thermal capacity of CO^2 is ~ 38% less than that of nitrogen, for example).
When a CO^2 molecule emits a photon, it moves into a less excited state (loses energy), and is therefore "cooler" than the surrounding gases at that moment. The surrounding gases then conduct some of their heat to the cooler CO^2 molecule via collisions, moving into less excited states themselves. So the fact CO^2 sheds energy via emission actually reduces the heat capacity of the atmosphere.