Did you build in error messages in your snippet? I think its more likely the snippet is firing but failing somehow rather than the events not firing, or maybe the snippet is not properly set up to fire on the event.
Also some code would help
Well the problem is OnDocFormSave is fired only when the document is saved via the admin, as the documentation says.
"Fires after a Resource is saved in the manager via the editing form."
And the same for OnDocPublished.
"Called when a Resource is published via the Publish context menu."
But when you set the time to Publish a document in the future (eg tomorrow), these events are not fired up.
I tested with sending a simple message every time you save a document, then every time you publish one. The Publish is not sending anything when I set the Publish date.
There is nothing to show really. I am just sending a curl JSON request to my Discord webhook.
I looked at the code in the modRequest class where this happens and it does not fire OnDocPublished, nor does it call the publish processor, which would fire that event. It should definitely do one or the other.
Could you file that as a feature request here: https://github.com/modxcms/revolution/issues