Apparently, my username randomly showed up on TI-Planet the other day with one of my files (Star Collector CE) associated with it, though I never signed up.
The download link also just redirects to Cemetech's download link.
If this is automatic, why only that file?
I'm not sure why this happened, but here is the link:
Account: https://tiplanet.org/forum/archives_list.php?ref=2120920&author=1&lang=en
File: https://tiplanet.org/forum/archives_voir.php?id=2120920

If someone could tell me why this happened, that would be great

Simple: critor made a front-page news article here about Star Collector CE: https://tiplanet.org/forum/viewtopic.php?t=22638. Since it's a download, an archive page for it (allowing info section, screenshot, links...) was created. Because there was no explicit license (apparently) allowing the re-upload, your file is simply linked from TI-Planet to Cemetech, since that's where it is right now. Hence why you noticed the redirect, as intended.

Also, https://tiplanet.org/forum/archives_list.php?ref=2120920&author=1 is not a TI-Planet account, it's simply a list of files whose author field is tagged as you.
If you want to have an actual account on TI-Planet, well you can create it, and we can bind this archive file to your account directly so that you can push updates to it by yourself without asking/waiting for approval, for instance.

This is the same for any other file/author we reference/link/news about, you[r game] just happen to be among the lucky ones to get a frontpage news article - we do monitor websites here and there about potential calculator news, so when your game became public (here, I presumed, but maybe someone else pointed him to it), critor deemed it would be nice to feature it

This explains it. Thanks!

I'd say that attempting to raise awareness about programs made elsewhere, in order to help expand the user base, is a custom in the French TI calculators community. Historically, various other sites and staffs have done that since before I started attending the international, then French TI calculators community in 2001
At TI-Planet, we attempt to link other sites when possible, unlike most other historical sites made by French people, on which the percentage of re-hosting was (much) higher. Re-hosting is great for building historical archives and preventing interesting content from disappearing - that's precisely what archive.org does - but of course, manual re-hosting can become outdated.

The disappearance of interesting content from its original source location over time is a fact:
* it did occur with some authors' work, e.g. Samuel Stearley's site ( http://www.calvin.edu/~sstear70 ) for the TI-68k series, which contained a number of unrivaled programs dealing with the CAS, a great periodic table, and more. There's http://www.stearley.org/calc.html , but that redirects to the aforementioned site, which has been 404 for over a decade. Fortunately, archive.org still has our back;
* just over the past week, third-party re-hosting of content from TI and Vernier, outside of TI-Planet, enabled me to get extra information about and programs for communicating with TI-Vernier lab equipment, for which I'm adding very limited support in libti*.