CFM is a measure of volume moved, generally quoted at effectively zero static pressure. Zero static pressure is rarely reality. All fans will have a static pressure vs airflow curve, which will vary based on the design of the fan.

I doubt normal people have the tools to measure fan CFM, especially when mounted into a product or enclosure, so presumably the OP was going based on stated specs.

On top of that low static pressure fans are generally quieter so if dB and CFM were their main criteria they probably didn't get the correct fans which is why I asked.