Diff drive controller publishing TFs and odometry with NANs

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In my launch file that I use to bring up my robot, I launch a robot_state_publisher and a diff_drive_controller. I have also configured my urdf such that I would expect the following TFs (from parent to child frame) in this order: odom -> base_footprint -> base_link

When I bring up my robot and run rosrun tf tf_echo base_footprint base_link I get the following error printed in the console:

At time 0.000
- Translation: [0.000, 0.000, 0.025]
- Rotation: in Quaternion [0.000, 0.000, 0.000, 1.000]
            in RPY (radian) [0.000, -0.000, 0.000]
            in RPY (degree) [0.000, -0.000, 0.000]
Error:   TF_NAN_INPUT: Ignoring transform for child_frame_id "base_footprint" from authority "unknown_publisher" because of a nan value in the transform (nan -nan 0.000000) (nan nan nan nan)

rostopic echo /odom reveals the following, that there are multiple nan's in the odom message (while the robot is not moving and no cmd_vels are being published)

  header: 
  seq: 455
  stamp: 
    secs: 1584298695
    nsecs:  56166660
  frame_id: "odom"
child_frame_id: "base_footprint"
pose: 
  pose: 
    position: 
      x: nan
      y: nan
      z: 0.0
    orientation: 
      x: nan
      y: nan
      z: nan
      w: nan
  covariance: [0.001, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.001, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1000000.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1000000.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1000000.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1000.0]
twist: 
  twist: 
    linear: 
      x: nan
      y: 0.0
      z: 0.0
    angular: 
      x: 0.0
      y: 0.0
      z: nan
  covariance: [0.001, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.001, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1000000.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1000000.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1000000.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1000.0]
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I've confirmed that it is definitely the diff_drive_controller that is causing the NAN problem by removing it from my launch file and using rosrun tf tf_echo base_footprint base_link to check if the error was still present, and it was not.

Furthermore, if I run the navigation stack both of these errors go away. However, they persist if I try to SLAM using gmapping. Has anyone else had this issue before? How can I fix diff_drive_controller to not publish NANs?

Here is a link to my repository, all of the relevant code is the the hw_interface (diff_drive_controller) and launch directories.