Banzai Cloud Index Dates

So far, for the most part, I am loving Banzai cloud in 2.5.x but that I cannot figure out is how to get it to send the indexes with a date next to them like it used to with the old ES.

I tried the below example but this sends nothing now, if I just use index_name it sends that with no date beside it. It seems like it should be something simple.

    host: <hostname redacted>
    include_timestamp: true
    logstash_dateformat: YYYY-MM-DD
    logstash_format: true
    logstash_prefix: perf-cluster-01
    port: 9200
    scheme: http