Robot_Localization EKF and Navsat_Transform node parameter configuration [closed]

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I am trying to configure the robot_localization nodes on the Clearpath Husky robot. I have set the robot up to use one copy each of navsat_transform_node and ekf_localization_node. On the husky, we have the following sensors publishing to the following topics:

Microstrain 3DM-GX2 IMU --> /imu/data Wheel encoding odometry --> /husky_velocity_controller/odom Garmin GPS puck --> /fix

Navsat_transform_node is set as follows:

Subscriptions: /imu/data, /odometry/filtered, /fix Publications: /odometry/gps, /gps/filtered

Ekf_localization_node is set as follows:

Subscriptions: /husky_velocity_controller/odom, /imu/data, /odometry/gps Publications: /odometry/filtered

My understanding is that the wheel husky_velocity_controller/odom and imu/data should begin spamming when everything is started and the messages on these topics should be fused in the EKF which should then spit out a /odometry/filtered message. The /imu/data and /odometry/filtered messages should go into navsat_transform_node which, once it receives its first /fix message from the GPS, should start spitting out its two message types.

When I run this on our Husky robot, the raw GPS fix gives nearly perfect positioning, but my /gps/filtered messages are returning coordinates that are all over the place. Most of the /gps/filtered points are near the correct path (although the path appears rotated and less neat than the raw /fix path), but there are a lot of places where the estimates jump very large distances. Also, the distances that the estimates jump appear to grow the longer the robot is run. I have a few questions:

1. Is /gps/filtered carrying the results of the data fusion and estimates in latitude and longitude? I.e., is this the message topic that I want to use for the robot's position estimate in actual latitude and longitude? If not, which message is and how must I prepare the data to be output into a .gpx file?
2. Are there parameters or reference frame settings that anyone can think of that might lead to the path jumps that I'm describing, or can anyone think of any reason why this might happen?

I wanted to include photos to help my description, but I'm not allowed.