rtabmap two odometry frames

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I am trying to use Intel Realsense t265 visual odometry camera with rtabmap on turtlebot3.

So, I have wheel odometry and camera odometry. t265 camera odometry uses wheel odometry as input. So, I need only camera odometry as input for doing SLAM.

Camera odometry frame is located where is camera located on the robot, on the top and front side. Wheel odometry is located on base_footprint

For rtabmap I set frame_id to base_link and odom input topic to /t265/odom/sample. When I run rviz I see that map is building around t265_odom_frame and base_link is located under the map.

Where is odometry frame should be placed on the robot for rtabmap? On the base_footprint place, right?

I suppose I should create new frame on the wheel odometry place, and write a script publishing camera odometry transformed from t265_odom_frame under this newly created frame. And then put this topic as input for rtabmap, am I right?