browser object

By its executable file name e.g. chrome.exe, msedge.exe and firefox.exe

Repeat:

Chromium as a standalone browser is not indicated as a supported browser for any version of TestComplete

https://support.smartbear.com/testcomplete/docs/app-testing/web/supported-browsers/index.html

Now, that said, I do understand that your colleagues, somehow, have gotten it to work.  How, I have not specific idea.  But here's a couple of things to look at:

1) Are they using Edge but, in someway, have it Edge itself configured to be recognized as Chromium instead of edge?
2) Do they have any custom plugins or anything that they are using?

Just an FYI, I tried downloading Chromium and running it as a browser and I get the same thing.  It is NOT supported as a web browser so I was honestly not expecting it to show up as a browser.

It will use the properties (assembly attributes) of the executable file name, if it's Chrome

Renaming Chrome,

Actual Chrome