Short Answer
Not directly — Casa Loyalty doesn't have a native "exclude this collection" setting. But you can get the same result using Excluded Product Tags, applied to every product in that collection.
How to Exclude a Collection (Workaround)
In Shopify Admin → Products, filter or open your collection's product list.
Select all products in that collection.
Use the bulk Add tags action to apply a shared tag (e.g., no-points) to all of them.
In Casa Loyalty → Settings → Platform → Excluded Product Tags, enable "Exclude reward points for products with any of these tags" and add the same tag (e.g., no-points).
Click Save.
Every product with that tag — effectively your whole collection — will now be skipped from points calculations.
Note
Any new product you add to the collection later will need the same tag applied for it to also be excluded — tagging is not automatically inherited from collection membership.