OK this is goofy. It works with a different rule. It won't accept some special characters and the rules remove them.

For example, creating the following rule removes the !
IF subject contains !onenote THEN forward TO me@onenote.com

After saving the rule you can see on screen the created rule is:
IF subject contains onenote THEN forward TO me@onenote.com (without !)

For some reason, the combo I had being *#* didn't convert and although it looks like it should work perfectly, I suspect it has something to do with being unable to use special characters.

I did numerous tests without special characters and all tests worked, eg:
IF subject contains 1note OR onenote THEN forward TO me@onenote.com

Hope this helps somebody out there, issue resolved. Emails appear in my OneNote now.