They are able to send the invites through the web client, but not through Outlook itself.

This leads me to believe that it is not a server issue, but rather a client issue.

Ive already uninstalled Office and reinstalled, but the problem still persists.

If its stuck in the outbox, open it and inspect it to see if everything is correct.

Assume two requests are made to a user who is out of the office for the same time.

The user can just select the one they wish to accept when they return.

Any meeting invites that are created in house are fine, and can be forwarded anywhere.

If it was already accepted you will find it in the initial recipients deleted items folder.

Or setup a rule for inbound invitations coming from specified users to be redirected or copied or moved to the appropriate inbox.

That recipient will see it pop up in their inbox over Outlook 2011.

Outlook Forward Meeting Invite Update To The

They can then accept and the update to the invite list will occur as it does in the Windows Client, notifying the intvitor of the new invitee.

Outlook For Mac Forward Meeting Invite