You can easily filter for Catalog orders from Shopify. Below are instructions on how to do so, as well as a video walkthrough.
Filter to see Catalog orders
Go to Shopify Orders.
Select Filter > Apps.
Select Rokt for Brands.
Video demo for how to filter for Catalog (formerly Canal) orders on Shopify:
To see Retailer details, download filtered orders to CSV:
Click Export after filtering orders to those from Catalog.
In the CSV file, review the "Note Attributes" column, which will contain the Partner(s) name.
Filter by Partner as needed.