How to have more than 1 of the same sensor types in obstacle layer of local costmap?

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I am trying to use 2 topics from RTABmap/obstacle_detection (obstacle, ground). Ground for the clearing and obstacle for marking.

I am trying to follow this answer, and am not sure if I am doing it right.

Below are my costmap params, I think i have it setup right but it looks like my local costmap is not updating, while my global costmap is. In my node graph it shows /ground being published to move_base but not /obstacles. Thanks!

local_costmap:
      global_frame: odom
      robot_base_frame: base_link
      update_frequency: 15.0
      publish_frequency: 15.0
      static_map: false
      rolling_window: true
      width: 8.0
      height: 8.0
      resolution: 0.025
      origin_x: -2.0
      origin_y: -2.0
  plugins:
  - {name: obstacle_layer, type: "costmap_2d::VoxelLayer"}

  obstacle_layer:
    observation_sources: point_cloud_sensor laser_scan_sensor
    point_cloud_sensor: {
      sensor_frame: base_link,
      data_type: PointCloud2, 
      topic: /obstacles, 
      expected_update_rate: 0.5, 
      marking: true, 
  clearing: false,
  min_obstacle_height: -99999.0,
  max_obstacle_height: 99999.0}
point_cloud_sensor: {
  sensor_frame: base_link,
  data_type: PointCloud2, 
  topic: /ground, 
  expected_update_rate: 0.5, 
  marking: false, 
  clearing: true,
  min_obstacle_height: -99999.0,
  max_obstacle_height: 99999.0
}

Global:

    global_costmap:
      global_frame: map
      robot_base_frame: base_link
      update_frequency: 15
      publish_frequency: 10
      static_map: true

Common:

obstacle_range: 4
raytrace_range: 6
footprint: [[-0.6858, -0.762], [-0.6858, 0.762], [0.6858, 0.762], [0.6858, -0.762]]
map_topic: map
footprint_padding: 0.03
robot_radius: 1.1
inflation_radius: 0.35
transform_tolerance: 1

    controller_patience: 2.0

    NavfnROS:
      allow_unknown: true

    plugins:
  - {name: static_layer, type: "costmap_2d::StaticLayer"}
  - {name: obstacle_layer, type: "costmap_2d::VoxelLayer"}
  - {name: inflation_layer, type: "costmap_2d::InflationLayer"}
recovery_behaviors: [
    {name: conservative_clear, type: clear_costmap_recovery/ClearCostmapRecovery},
    {name: aggressive_clear, type: clear_costmap_recovery/ClearCostmapRecovery}
]

conservative_clear: 
    reset_distance: 3.00
aggressive_clear:
    reset_distance: 1.84