Elasticsearch GeoIP Processor inside foreach processor


I'm running an 8.3.2 cluster, and I have an array containing some objects over which I'd like to iterate and enrich with the GeoIP processor, but am having limited success.

I have a foreach processor set up with a geoip processor inside it. The GeoIP processor receives the _ingest._value correctly, but I seemingly cannot add the looked-up information to the current object.

If I set the target_field to simply "geo", the information appears but in the root of the JSON structure, whereas I need it added on a per-iterated-object basis instead.

Is there something that I'm overlooking? Here's a snippet of the document I'm working with:

        "answers": [
            "recordTypeId": 1,
            "domainName": "blah.com",
            "rData": "",
            "class": 1,
            "ttl": 60

and the processor:

    "foreach": {
      "field": "path.to.answers",
      "processor": {
        "geoip": {
          "field": "_ingest._value.rData",
          "target_field": "_ingest_value.geo",
          "database_file": "GeoLite2-ASN.mmdb",
          "properties": [
          "first_only": false,
          "ignore_missing": false

Thanks in advance!