ICM-42688-P timebase correction

In the previous ICM20948, ICM20648 and ICM20649 there was a TIMEBASE_CORRECTION_PLL register containing the imperfection in the PLL clock. Now I know that with the ICM-42688-P you can connect an external crystal, but currently we don't have the option to add that. We would still like to compensate for the internal imperfections of the PLL clock, but there is no register anymore containing the timebase correction.
Is there some hidden register still containing this information? Why is this removed from the ICM42688?