Neptune Signed IAM URL Expiry

I'm trying to work with Neptune and Spark, following the Iam authentication guides. However, I have a large dataset I'm working with that I'd like to write with the neo4j spark connector, but this would take longer than the 5 minute expiry of the authenticated URL. I have no problems when I add on the X-Amz-Expires tag to a HTTPS request (like going to /status endpoint), however when I try with bolt I have never had success, below is my class that is failing. Is the expires tag supported for this, or am I forced to exit spark and instead use the credential refreshing provided by Neo4j?

The URL I'm attempting to hit is of the format bolt://{cluster_endpoint}:8182/opencypher

class NeptuneAuthToken(Auth):
  def __init__(
    self,
    credentials: Credentials,
    region: str,
    url: str,
    with_expire: bool = True,
    **parameters
  ):
    # Do NOT add "/opencypher" in the line below if you're using an engine version older than 1.2.0.0
    request = AWSRequest(method=HTTP_METHOD, url=url)
    request.headers.add_header("Host", _host_from_url(request.url))
    if with_expire:
      request.headers.add_header(X_AMZ_EXPIRES, "1200")
    sigv4 = SigV4Auth(credentials, SERVICE_NAME, "us-west-2")
    sigv4.add_auth(request)

    auth_obj = {
      hdr: request.headers[hdr]
      for hdr in [AUTHORIZATION, X_AMZ_DATE, X_AMZ_SECURITY_TOKEN, HOST] + ([X_AMZ_EXPIRES] if with_expire else [])
    }
    auth_obj[HTTP_METHOD_HDR] = request.method
    creds: str = json.dumps(auth_obj)
    super().__init__(SCHEME, DUMMY_USERNAME, creds, REALM, **parameters)