How to merge multiple Google Slides?

Given a Google Drive folder containing multiple Google Slides files (which may have multiple object slides within them), how would you combine them all into one Slides file?

So far, I’ve got this…

(ie. I iterate through all Slides files and, within each, through all slide object/page. I started by creating a new blank presentation to be used as target).

The trouble is, neither module…

  1. Create a Presentation from Template
  2. Create a Slide from a Template Slide

… seems correct, because:

  • Create a Presentation from Template” only replicates a whole Google Slides file.
  • Create a Slide from a Template Slide” will only allow duplication of a slide object (individual page) within its same Slides presentation. Since the source object ID does not exist within the target Slides file, it cannot be duplicated.

Any ideas to work around this, pleaes?