Webhook/real-time updates for changes in Facebook ads/adsets/campaign

Question

I couldn't find a straight-forward webhook in Facebook's documentation for getting updates in real-time whenever anything changes in Facebook ads manager - Ads/AdSets/Campaign to be precise.

I also looked into ad rules engine - but that too isn't sending updates.

Here's the ad rules trigger I'm testing with:

{
  "id": "<redacted>",
  "name": "METADATA_UPDATE Example 1",
  "evaluation_spec": {
    "evaluation_type": "TRIGGER",
    "filters": [
      {
        "field": "entity_type",
        "value": "CAMPAIGN",
        "operator": "EQUAL"
      }
    ],
    "trigger": {
      "type": "METADATA_UPDATE",
      "field": "name"
    }
  },
  "execution_spec": {
    "execution_type": "PING_ENDPOINT"
  },
  "status": "ENABLED",
  "account_id": "<redacted>"
}

I've also subscribed to ads_rules_engine in application webhooks. "Test" works fine, but I'm not getting any hits to the webhook URL if I change name of a campaign in ads manager.

What am I missing, or am I looking in the wrong direction?