Just to explain a little bit about meteor npm package:
Meteor NPM package is just an installer, it’s not really Meteor so its version is not that important. You can install any version of the installer and later use meteor itself to have a different version of it.
But I believe there is something else happening in your co-workers machine. I released 2.5 my self and I tested everything on Mac (I’m a Mac user) and I just re-tested everything and it’s working fine.
Could you post here what are the commands that they are running?
If you already upgraded Meteor they shouldn’t upgrade again as you are saying “Now my coworkers can’t upgrade with the following error”. They should just run the app and Meteor should get the new version automatically.
My coworkers doesn’t run the update command first, only meteor run the download didn’t seems to start and failed (no network usage).
We found a workaround we uninstall/reinstall meteor on their machine.
With this workaround the meteor run command successfully download the 2.5 version.
We also tried to create a new meteor app in a temp dir it doesn’t work either (no download)