Is there a way to secure PDFs from editing while also enabling combine?

Our marketing team builds a set of standard flyers and secures them with a password so that the content cannot be edited outside of their control.

Units across the organization consuming these flyers would like to mix and match the flyers and combine them into a single PDF. 

Combining secured PDFs into a single PDF requires  the password - which marketing wants to restrict.

Combinine secured PDFs into a portfolio is achievable without the password, but then does not generate the desired of a single PDF. Consumers may combine 100s of flyers and the step to individually open files in the portfolio is not desired if it can be avoided.

There appears to be a Document Assembly - Allowed/Not Allowed restriction in the Security Summary.

Is there a way to set permissions and restrict editing, while allowing document assembly (which I assume connects to the Combine function)?