SendGrid API how to view Event Hooks

I’ve been using the standard tutorial for SendGrid with Wix and its great in every way except that my custom_args arent being used in the Emails. (I’m getting code 202 so the emails are being sent, they just dont have the custom_arg data filled in on the emails)
I saw a post talking about their Event Hooks where you could see data like

    "email": "",
    "timestamp": 1513299569,
    "smtp-id": "<14c5d75ce93.dfd.64b469@ismtpd-555>",
    "event": "processed",
    "category": "cat facts",
    "loc": "Cat Sanctuary",
    "sg_event_id": "sg_event_id",
    "sg_message_id": "sg_message_id"

But nothing shows up in my “return” json that comes back from the API that resembles this where the last three things in the json are included in the custom arguments.
How do you view this data?

Return JSON:

  "url": "",
  "status": 202,
  "statusText": "Accepted",
  "headers": {
    "_headers": {
      "server": [
      "date": [
        "Tue, 10 Nov 2020 15:21:24 GMT"
      "content-length": [
      "connection": [
      "x-message-id": [
      "access-control-allow-origin": [
      "access-control-allow-methods": [
      "access-control-allow-headers": [
        "Authorization, Content-Type, On-behalf-of, x-sg-elas-acl"
      "access-control-max-age": [
      "x-no-cors-reason": [
  "ok": true,
  "body": {
    "_readableState": {
      "objectMode": false,
      "highWaterMark": 16384,
      "buffer": {
        "head": null,
        "tail": null,
        "length": 0
      "length": 0,
      "pipes": null,
      "pipesCount": 0,
      "flowing": null,
      "ended": true,
      "endEmitted": false,
      "reading": false,
      "sync": false,
      "needReadable": false,
      "emittedReadable": false,
      "readableListening": false,
      "resumeScheduled": false,
      "paused": true,
      "emitClose": true,
      "autoDestroy": false,
      "destroyed": false,
      "defaultEncoding": "utf8",
      "awaitDrain": 0,
      "readingMore": false,
      "decoder": null,
      "encoding": null
    "readable": true,
    "_events": {},
    "_eventsCount": 1,
    "_writableState": {
      "objectMode": false,
      "highWaterMark": 16384,
      "finalCalled": false,
      "needDrain": false,
      "ending": true,
      "ended": true,
      "finished": true,
      "destroyed": false,
      "decodeStrings": true,
      "defaultEncoding": "utf8",
      "length": 0,
      "writing": false,
      "corked": 0,
      "sync": true,
      "bufferProcessing": false,
      "writecb": null,
      "writelen": 0,
      "bufferedRequest": null,
      "lastBufferedRequest": null,
      "pendingcb": 0,
      "prefinished": true,
      "errorEmitted": false,
      "emitClose": true,
      "autoDestroy": false,
      "bufferedRequestCount": 0,
      "corkedRequestsFree": {
        "next": null,
        "entry": null
    "writable": false,
    "allowHalfOpen": true,
    "_transformState": {
      "needTransform": false,
      "transforming": false,
      "writecb": null,
      "writechunk": null,
      "writeencoding": null
  "bodyUsed": false,
  "size": 0,
  "timeout": 0,
  "_raw": [],
  "_abort": false

As you can see from my return data “_events”: {} which was where I thought I would find this data.
Any ideas?