Intel's Euclid kit (a candy bar sized mini PC with a RealSense ZR300 camera in) could use ORB_SLAM2, so there are some references to how to configure yaml if you google for 'intel euclid yaml'. You may be able to adapt these for using ORB_SLAM2 with D415.
For example, the link below is a discussion about using ZR300 with ORB_SLAM2 and the configuring of the yaml file.
This other guide may be useful too. It makes reference to example yaml files in a folder called ORB/Examples/Mono/ - I'm guessing this is one of the folders in the ORB_SLAM2 package.
The above guide recommends that ORB_SLAM2 users should calibrate their camera.