When you need to create an order on behalf of a customer, you can create a draft order in your Shopify admin.
How can I make a draft order with a bundle product?
If you make a bundle as a product and set it to "Add the bundle as a product to the cart as a single product" or Single-BAP, you can use it for draft orders.
In other cases, unfortunately, the Fast Bundle automatic discounts won't be applied to the draft orders. You can read about the differences between the two types of bundle as products here.
