This stores Greenroom's rosdep lists.
Add 30-greenroom.list to your /etc/ros/rosdep/sources.list.d
sudo wget -O /etc/ros/rosdep/sources.list.d/30-greenroom.list https://raw.githubusercontent.com/Greenroom-Robotics/rosdistro/main/rosdep/sources.list.d/30-greenroom.list