As noted in the previous post ideal gas behavior is approximated when there is no liquid in the bottle i.e. when it has all boiled off at a temperature below critical or when above critical but to say that the gas law applies to a 2 phase system one of which is coalesced seems a bit of a stretch. The gas over the liquid would follow the gas law (approximately) but certainly not the system as the gas law says that the pressure is proportional to temperature and amount of material in the container. As noted in the earlier post the pressure does not depend on the amount of liquid in the bottle when liquid is present.
Also the gas law implies linear dependence of pressure on temperature (constant volume, constant mass). The best linear fit to the vapor pressure of CO2 between 0 °F and the critical temperaure has peak errors of 30 psi at both ends (10% at the low end, 3% at the high end). A second order fit gets residuals down to less than 1 psi across the range. Given that the cheapie high pressure gauges on most regulators are probably only accurate to 10% its probaly OK to write Pvap = -3340.9 + 14.145*T (T in Kelvins) i.e. to linearize it but the value at T = 0 makes it obvious that it is not the ideal gas law at work when both phases are present.