rqt_plugin launched from launch file on x-server

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I am using ROS kinetic Ubuntu 16.04, QT Creator 4.8.1, based on QT 5.12.

Currently I am running a ROS program using VNC. Running rqt on it's own has not been possible due to an x-server error which is related to the fact that it is running the vncserver. An rqt standalone plugin does launch when called from the command line. However, it would be preferable if the rqt plugin could be launched using the main Launch file. Currently I am trying to launch it with this launch file

<launch>
    <include file="$(find coord_proces)/launch/img_proc_calib.launch"/>
    <include file="$(find cobot)/Launch/cobot_node.launch"/>
    <node pkg="transport" type="transport_node.py" name="transport_node" output="screen"/>
    <node pkg="control" type="control_node.py" name="control_node" output="screen"/>
    <node pkg="$(find rqt_visualization)" type="rqt_visualization" name="rqt_visualization"/>
</launch>

per this example: https://answers.ros.org/question/3157...

rqt_visualization has the following script inside it:

#!/usr/bin/env python

import sys

from rqt_visualization.my_module import MyPlugin
from rqt_gui.main import Main

plugin = 'rqt_visualization'
main = Main(filename=plugin)
sys.exit(main.main(standalone=plugin))

launching the launch file returns the following error message:

 ERROR: cannot launch node of type [/home/thomas/GIT/automatic-planthandling/Ros/catkin_ws/src/rqt_visualization/rqt_visualization]: /home/thomas/GIT/automatic-planthandling/Ros/catkin_ws/src/rqt_visualization

I am able to launch the combination of launch files and node separately. Running rqt using with

rqt -s rqt_visualization

From what i have found the rqt_visualization script should be run as any other node, however this does not work. Would the call in the launch file need to be changed? Could this problem be related to a deeper lying issue?