tf2 Transform using FSD(NED like) frame return incorrect value

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I have a underwater robot that we would like to use Forward, Port, Down orientation. I thought I could just create a link with flipped vertices.

The urdf below displays correctly in rviz

When I create a tf2 listener and try to transform a point from "depth_sensor" to "body-fixed" frames I get the wrong answer.

My script uses a Z of 10 in the depth_sensor frame and returns 5 in the body-fixed frame when I would expect it to return 15

I am obviously missing something.

test.urdf <robot name="robot"> <link name="map"> </link>

    <joint name="base" type="floating">
        <origin rpy="0 0 0" xyz="0 0 0"/>
        <parent link="map"/>
        <child link="base"/>
    </joint>

    <link name="base">
     </link>

    <joint name="vehicle" type="fixed">
        <origin rpy="3.14159265359 0 0" xyz="0 0 0"/>
        <parent link="base"/>
        <child link="vehicle"/>
    </joint>

    <link name="vehicle">
    </link>

    <joint name="depth_sensor" type="fixed">
         <origin rpy="0 0 0" xyz="0 0 5"/>
        <parent link="vehicle"/>
        <child link="depth_sensor"/>
    </joint>

    <link name="depth_sensor">
    </link>

    <joint name="body-fixed" type="fixed">
         <origin rpy="0 0 0" xyz="0 0 10"/>
        <parent link="vehicle"/>
        <child link="body-fixed"/>
    </joint>

    <link name="body-fixed">
    </link>

</robot>

listener.py

#!/usr/bin/env python  
import rospy
import math
import tf2_ros
import geometry_msgs.msg
import tf2_geometry_msgs
from geometry_msgs.msg import PointStamped
if __name__ == '__main__':
    rospy.init_node('listener')
    tfBuffer = tf2_ros.Buffer()
    listener = tf2_ros.TransformListener(tfBuffer)
    rate = rospy.Rate(1.0)
    value = PointStamped()
    value.header.frame_id = "depth_sensor"
    value.point.x  = 0.0
    value.point.y = 0.0
    value.point.z = 10.0
    rospy.loginfo(value)

    while not rospy.is_shutdown():
        try:
            trans = tfBuffer.lookup_transform("body-fixed", 'depth_sensor', rospy.Time())
        except (tf2_ros.LookupException, tf2_ros.ConnectivityException, tf2_ros.ExtrapolationException):
            rospy.logerr("No transform")
            rate.sleep()
            continue

        rospy.loginfo(trans)

        value2 = tf2_geometry_msgs.do_transform_point(value, trans) 
        rospy.loginfo(value2)
        break

rviz.launch

<launch> <arg name="gui" default="True"/> <node name="robot_state_publisher" pkg="robot_state_publisher" type="state_publisher"/>

<!-- rviz with 3rd person view -->
<node name="rviz01" pkg="rviz" type="rviz" args="-d $(find viztools)/config/test.rviz" required="true" />

<node pkg="tf" type="static_transform_publisher" name="map2vehicle" args="0.0, 0.0, 0.0, 0.00, 0.00, 0.00, 1 map base 50" />

</launch>

output

[INFO] [1508248990.598399]: header: 
  seq: 0
  stamp: 
    secs: 0
    nsecs:         0
  frame_id: depth_sensor
point: 
  x: 0.0
  y: 0.0
  z: 10.0
[ERROR] [1508248990.599694]: No transform
[INFO] [1508248991.598975]: header: 
  seq: 0
  stamp: 
    secs: 0
    nsecs:         0
  frame_id: body-fixed
child_frame_id: depth_sensor
transform: 
  translation: 
    x: 0.0
    y: 0.0
    z: -5.0
  rotation: 
    x: 0.0
    y: 0.0
    z: 0.0
    w: 1.0
[INFO] [1508248991.601145]: header: 
  seq: 0
  stamp: 
    secs: 0
    nsecs:         0
  frame_id: body-fixed
point: 
  x: 0.0
  y: 0.0
  z: 5.0