As that thread is 6 years old at this point, anything hosted on DropBox is probably long gone.
We have had an increase of Halo 2 Anniversary ODSTS recently, and many of them recommend the Titlewave files:
These are paid 3D Printing files, but they also include integrated strapping mounting points and images of strapping guides.
If you are more interested in the Pepakura or Foam route, we do have the helmet files in the Armory for those methods:
This is a comprehensive zip file including numerous files from multiple artists. Contents of zip-file: halo-2-anniversary-unsc-odst-helmet.pdo Modeler: Satchmo III PRINTABLE FILES halo-2-anniversary-unsc-odst-helmet.stl Modeler: Satchmo III
www.405th.com
Back in 2021 another member started making the rest of the armor in Pepakura. They did not complete the project, but did post their files that they had completed before abandoning the costume:
I've known about 405th for awhile, but it wasn't until now I decided to scroll through the threads. Recently I've gotten into the ODSTs more than the Spartans, but I more specifically gotten into the Halo 2 (Anniversary) ODSTs. For some reason, I find them a bit more appealing than the Halo 3...
www.405th.com
Here is a very comprehensive Anniversary ODST planning and information thread:
INTRO: REFERENCE THREADS, FILES AND OVERALL DETAILS MY GOAL WITH THIS THREAD IS: To document my journey as explicitly and thorough as possible, with as many photos as possible and a cost/time breakdown spreadsheet. (please note that I am Australian, and will be pricing everything in AUD)...
www.405th.com