Hi Matt, Houzz is currently supported by the listing section in Snapshot Report. As long as the account has its first business category as either Home Services, Local Services, or Event Services, it should show up under their listings.
If it's not showing up, then you may need to edit the business categories for that account. This can be done in their account details. I would suggest clearing all the account's current business categories, and only selecting homes services to ensure the listings update correctly.
Once you've updated the account details, the Snapshot Report should automatically refresh and begin reviewing the listings under that new business category which should include Houzz. I hope that helps, don't hesitate to let me know if you have any additional questions about this.