Universal Containers (UC) wants to make a marketing newsletter and directly use data from five unrelated objects (two standard and three custom) in a prompt template. How should UC accomplish this?

Flex templates are specifically architected to accept multiple Salesforce objects - both standard and custom - as independent inputs in a single prompt template, which is the only native template type that supports this multi-object pattern. This makes flex templates the direct solution for referencing data from five unrelated objects without custom code or workarounds.

Creating a custom object to temporarily connect unrelated records introduces unnecessary schema complexity and is not a supported Salesforce pattern for multi-object prompt template access.

Using a flow to retrieve data adds automation indirection and does not leverage the native multi-object input capability that flex templates already provide.