Email to Case Queue Misbehaving

After quite a bit of reading and frustration, I finally got an email-to-case system configured for our service desk.  I followed this guide pretty much to the letter, although there are a few gaps in the guide if you're on a fresh provision of Dynamics Online:

https://www.microsoft.com/en-us/dynamics/crm-customer-center/automatically-create-a-case-from-an-email.aspx

We configured the following:

1. Created an Queue called "Internal Helpdesk", configured it to use an O365 account with server-side email syncing. 

2. Created a Record Creation and Update Rule pointing to the "Internal Helpdesk" queue

3. Created a "Specify Record Creation and Update Details" item to create a Case

Again, this is all per the guide referenced in the link above.  So Dynamics is properly harvesting the emails coming into the mailbox, but the issue is that it's not routing the cases to the "Internal Helpdesk" queue.  Which is really strange because it seems to be properly sending the response email which is attached to the queue configuration. 

We also tried deleting the "Specify Record Creation and Update Details" item that creates the case in hopes that there was some default behavior we were accidentally over-riding.  But after making that change it stopped creating cases all together.

Any ideas what we're missing here?  The end-goal is to have it automatically create the case and assign it to the "Internal Helpdesk" queue.

Thanks,

- Jeff

- Jeff