An IP user made some translation edits to a couple of pages. They removed a fuzzy indicator, but also edited the translated text itself. There is, however, no translation unit shown in their contribution (or deleted contributions). Looking at one of the pages they edited, I can find the actual unit that was modified through the edit history of another editor of that page, but the unit's history does not match the page edit history---according to the page history Shirayuki restored the malformed variable translation, but in the unit history it shows Shirayuki's edit as (sort of) the opposite, and it also does not include the IP edits.
How did they perform those edits, and why is it not properly recorded in the unit history?