Trigger outgoing webhook from incoming webhook

Hi!
I have the same situation under the below link.

Outgoing webhook not launched after an Incoming Webhook is called · Issue #16238 · mattermost/mattermost (github.com)

My expect process from mattermost:

  1. grafana send alert to mattermost through incoming webhook
  2. mattermost receive alert from incoming webhook
  3. mattermost send some message to callback url (my automated testing server) configured from outgoing webhook.
  4. call url (my automated testing server) received some message from mattermost. and do something based on some message.

I tested the above steps. and then I finally figure out that step 3 never happens.
Incoming & outgoing webhook runs perfectly. but incoming webhook might not be connected with outgoing webhook.

Can the latest mattermost support the outgoing webhook from incoming webhook?