Regarding the Pose:
When using the MLSDK APIs with OpenXR , you will need to set the App into Unbounded tracking space. As mentioned here : MLCamera | MagicLeap Developer Documentation
This is because the MLSDK returns a Pose in a diferent space which is the equivalent of OpenXR’s unbounded.
Regarding the Depth Camera API:
Please note, the MLSDK API (MLDepthCamera) has been deprecated in favor of the OpenXR Magic Leap Pixel Sensor API. This means that the API will not receive updates and is no longer supported. That said, here is an old post regarding the ML Depth Camera: