It is your assertion so it is up to you to evidence it. Please show how this vapor canopy produces the evidence we see, such as the U/Pb ratios we see in zircons or the K/Ar ratios that we see in meteorites.
To further expand on this, Buzsaw would also need to explain how the vapour canopy on the Earth affected the radiometric dating of Lunar rock samples and why oldest crustal samples from both the Earth and the moon give similar ages.