Cool idea to use brackets.
Another idea might be to use a custom font that has both numbers and a square box.

Or (this is crazy, but it works) you could fake a square by applying a rule above and a rule below to the paragraph, and set the positioning and thickness of the rules so that one “knocks out” the other, except for an outline of a square in the proper location.

Data Merge doesn’t normally do tables, but this script can help:
https://creativepro.com/using-data-merge-to-create-a-table-for-a-directory.php

I show it in my title on Data Merge and database publishing at Lynda.com

I don’t think InDesign can do it without help: https://creativepro.com/quick-what-pantone-color-is-that.php

Does this article help?
https://creativepro.com/arranging-numbered-lists-separate-frames.php

Hi Jon,
Does it have to be specifically 2048? Are all the images the same width in InDesign now?
I wonder if perhaps setting a specific output resolution in Object > Image Export Options would work.