Femto Bolt imu to rgb extrinsics

I need the imu to rgb extrinsics for the Femto Bolt camera. So far I tried getting them with the OrbbecROS SDK, where one can see the topics
/camera/depth_to_accel and /camera/depth_to_gyro, both of which return empty matrices. Is this info provided by the Orbbec SDK at all and if not, has someone done the calibration locally already?

Thanks in advance!