turtlebot2 gmapping demo problem

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when I roslaunch turtlebot_navigation gmapping_demo.launch I get this error:

while processing /opt/ros/kinetic/share/turtlebot_bringup/launch/3dsensor.launch:
while processing /opt/ros/kinetic/share/turtlebot_bringup/launch/includes/3dsensor/d435.launch.xml:
while processing opt/ros/kinetic/share/realsense2_camera/launch/rs_d435_camera_with_model.launch:
Invalid roslaunch XML syntax: [Errno 2] No such file or directory: u'opt/ros/kinetic/share/realsense2_camera/launch/rs_d435_camera_with_model.launch'
The traceback for the exception was written to the log file

The file in question(d435.launch.xml) is this:

<launch>
<!--
 "camera" should uniquely identify the device. All topics are pushed down
       into the "camera" namespace, and it is prepended to tf frame ids. 
-->
<arg name="camera" default="camera"/>
<arg name="publish_tf" default="false"/>
<!--
 Factory-calibrated depth registration 
       NOTE: HW Registration not supported by R200 camera 
-->
<arg name="depth_registration" default="false"/>
<arg if="$(arg depth_registration)" name="depth" value="depth_registered"/>
<arg unless="$(arg depth_registration)" name="depth" value="depth"/>
<!-- Processing Modules -->
<arg name="rgb_processing" default="true"/>
<arg name="ir_processing" default="true"/>
<arg name="depth_processing" default="true"/>
<arg name="depth_registered_processing" default="true"/>
<arg name="disparity_processing" default="true"/>
<arg name="disparity_registered_processing" default="true"/>
<arg name="scan_processing" default="true"/>
<!-- Worker threads for the nodelet manager -->
<arg name="num_worker_threads" default="4"/>
<include file="opt/ros/kinetic/share/realsense2_camera/launch/rs_d435_camera_with_model.launch">
<arg name="camera" value="$(arg camera)"/>
<arg name="camera_type" value="d435"/>
<arg name="publish_tf" value="$(arg publish_tf)"/>
<arg name="num_worker_threads" value="$(arg num_worker_threads)"/>
<!-- Processing Modules -->
<arg name="rgb_processing" value="$(arg rgb_processing)"/>
<arg name="ir_processing" value="$(arg ir_processing)"/>
<arg name="depth_processing" value="$(arg depth_processing)"/>
<arg name="depth_registered_processing" value="$(arg depth_registered_processing)"/>
<arg name="disparity_processing" value="$(arg disparity_processing)"/>
<arg name="disparity_registered_processing" value="$(arg disparity_registered_processing)"/>
</include>
</launch>

The file the error says is missing, is in actuality, not missing at all. This is the file:

<launch>
  <arg name="serial_no"           default=""/>
  <arg name="json_file_path"      default=""/>
  <arg name="camera"              default="camera"/>
  <arg name="tf_prefix"           default="$(arg camera)"/>
  <arg name="external_manager"    default="false"/>
  <arg name="manager"             default="realsense2_camera_manager"/>

  <arg name="fisheye_width"       default="640"/>
  <arg name="fisheye_height"      default="480"/>
  <arg name="enable_fisheye"      default="false"/>

  <arg name="depth_width"         default="640"/>
  <arg name="depth_height"        default="480"/>
  <arg name="enable_depth"        default="true"/>

  <arg name="infra_width"        default="640"/>
  <arg name="infra_height"       default="480"/>
  <arg name="enable_infra1"       default="true"/>
  <arg name="enable_infra2"       default="true"/>

  <arg name="color_width"         default="640"/>
  <arg name="color_height"        default="480"/>
  <arg name="enable_color"        default="true"/>

  <arg name="fisheye_fps"         default="30"/>
  <arg name="depth_fps"           default="30"/>
  <arg name="infra_fps"           default="30"/>
  <arg name="color_fps"           default="30"/>
  <arg name="gyro_fps"            default="400"/>
  <arg name="accel_fps"           default="250"/>
  <arg name="enable_gyro"         default="true"/>
  <arg name="enable_accel"        default="true"/>

  <arg name="enable_pointcloud"         default="false"/>
  <arg name="pointcloud_texture_stream" default="RS2_STREAM_COLOR"/>
  <arg name ...