You can do this by going to Setup->Categories and scrolling down towards the bottom. There is a setting there where you can turn on a notification to a user or group of users if there is no default assignee on the ticket.
Here is a post that talks about the hierarchy of how the system assigns tickets too in case it helps: Product Update: Site/Department-based routing of incidents
You wrote:"Also, I was told by support yesterday that the "Notify assignee when a new task is created" setting has to be enabled in order for approval emails to be sent. This is causing the incident assignee to get a new email for each and every one of the 20 something tasks in our workflow. "
I had a similar suggestion in the post below. you might want to up vote it.
Ability turn off email notifications for service catalog on a per task basis
I have the "Notify assignee when a new task is created" enabled, and have a hack to prevent too many notices from being sent. I've created a group with no members in it. Tasks that I do not want to generate email notices are assigned to this group.
Hi, David - we are just implementing Samanage and face the same challenges you face with the excessive email notices. I tried your approach (created a No email group with no members), but my workflow stalls at those tasks, and I can't seem to move past them, even though I have the incident assigned to me. Did you run into this issue, and if yes, how did you resolve it? Thanks so much -
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