Sink Connector does not copy "record key" into SPLUNK

[bluedog13]

While running the sink connector I noticed that the record "key" was not being logged into SPLUNK. Is there anything specific that needs to be done to record the "key".

The message offset, the message headers are available in SPLUNK as expected - the below has been used in the config file

"splunk.hec.track.data"  : "true",

The entire config file is

{
    "name"                                      : "[redacted]",
    "topics"                                    : "[redacted]",
    "input.data.format"                         : "[redacted]",
    "connector.class"                           : "SplunkSink",
    "kafka.auth.mode"                           : "KAFKA_API_KEY",
    "kafka.api.key"                             : "[redacted]",
    "kafka.api.secret"                          : "[redacted]",
    "splunk.hec.uri"                            : "https://splunk.[redacted].io:443",
    "splunk.hec.token"                          : "[redacted]",
    "splunk.indexes"                            : "[redacted]",
    "splunk.sources"                            : "[redacted]",
    "splunk.hec.ssl.validate.certs"             : "false",
    "splunk.hec.raw"                            : "false",
    "splunk.hec.track.data"                     : "true",
    "splunk.hec.http.keepalive"                 : "true",
    "splunk.hec.max.http.connection.per.channel": "2",
    "splunk.hec.total.channels"                 : "2",
    "splunk.hec.socket.timeout"                 : "60",
    "splunk.hec.use.record.timestamp"           : "true",
    "splunk.hec.threads"                        : "1",
    "splunk.hec.max.outstanding.events"         : "10000",
    "splunk.hec.max.retries"                    : "5",
    "splunk.hec.backoff.threshhold.seconds"     : "60",
    "splunk.hec.json.event.formatted"           : "false",
    "splunk.hec.max.batch.size"                 : "500",
    "splunk.hec.lb.poll.interval"               : "120",
    "splunk.flush.window"                       : "10",
    "splunk.hec.ack.enabled"                    : "false",
    "splunk.header.support"                     : "true",
    "tasks.max"                                 : "3"
}

Much appreciated.