The advice we get from Boeing is that because of the sampling rate, the location of the sensors and the various resonances you get in the structure on touchdown, the QAR ‘g’ data is not that reliable. I guess the same would probably apply to any other manufacturer. If you think you did a heavy landing, report it as it may not show up on FOQA. Equally, something that flags up on a data trawl may not have been anything near as heavy as it shows...
I’m sure your company are well aware of this.