How to dynamically set environment variables in a docker-entrypoint.sh?

I have a go binary that will pull environment variables from AWS SSM Param, when the script runs, it prints out lines like this:

export FOO="BAR"
export BAZ="QUX"

This works well and I actually see the print happening. Then, I have a docker-entrypoint.sh shell file that takes these lines and eval's them, setting triggering the export:

#!/bin/bash
set -e

ssm_available() {
  if [ -z "$SSM_BASE_PATH" ]; then
    return 1
  fi

  return 0
}

export_ssm_params_go() {
  set -x
  eval $(./ssm_get_parameter --path ${SSM_BASE_PATH})
  exec "$@"
}

main() {
  if ssm_available; then
    echo "Info: Loading SSM Parameters" >&2
    export_ssm_params_go "$@"
  fi

  echo "Info: Starting ..." >&2
  exec "$@"
}

main "$@"

I see that it works but it's not actually setting the env var when I exec into the container and run env. This is the output

Info: Loading SSM Parameters
+ ./ssm_get_parameter --path /p-stack-fs/env/production
+ eval export 'FOO="TEST"'
+ export 'FOO=TEST'
+ exec node server.js

I feel like maybe it's running in a subshell and setting that or something? Here's the end of my Dockerfile:

...
ENTRYPOINT [ "sh", "docker-entrypoint.sh" ]
CMD ["node", "server.js"]

EDIT: actually looks like it is setting it but when I try to run env in a docker exec command, it doesn't show up, even though the other ENV variables in my Dockerfiles does. Any idea why?