Note I work for Google and I've contributed to Chromium, though I'm not necessarily an expert on Chromium forks.

1. Google Chrome

This is offical Chrome you download from google.com and also comes on ChromeOS devices.

2. Chromium

This is what you get when someone builds Chromium from the official repo without access to confidential source.

Source is confidential for various reasons, and some code that seems should be confidential actually isn't, like Android-for-ChromeOS integration, some of which is here: https://crsrc.org/c/chrome/browser/ash/arc/

3. Ungoogled Chrome?

This seems a contradiction of terms. Only Google can build Chrome, so they are not likely to e.g. set Bing as default or remove Google password manager support.

4. Ungoogled Chromium?

A particular project run by a particular team which forks Chromium and removes pro-Google behavior and settings.

5. Googled Chromium?

I don't know the original context of the use of this term, but possibly this just refers to official Chrome.