Would it be possible to
1. change the sending domain to micosoft.com and or/
2. get the alias to pass the Outlook phish flags?
It's in Microsoft's best interests that the community platform be seen as a trusted platform by their own tools as well.
It's a 3rd party platform, there are certain limitations they have to respect. @Jeff Medford @Anna Chu might be able to share more detail here.
Thanks for letting us know @Susan Bradley we will investigate.