Pseudonimization is bad terminology in that it's indistinct from the above, to the point that parent has already mixed the two up while in the process of recommending it. And it'd be worse verbally.
"Pseudo-anonymization" could work, but something like "breakable anonymization" or "partial anonymization" might be better in that it's more obvious to a reader and doesn't rely on familiarity with technical terminology to convey the idea.
I'd go with breakable, myself, since it's most to the point about why it's a problem.
Pseudo is etymologically correct, but that doesn't necessarily help us much when the goal is ratio and ease of understanding by a wide population of readers.
Partial could work in the sense that you did part of the job, which people would hopefully understand is a bit like having locked the back door for the night while leaving the front propped wide open.
And there are probably other good options. If I was writing about this topic often, I'd strongly consider brainstorming a few more and running a user test where I ask random people to explain each term, then go with what consistently gets results closest to what I'm trying to discuss.
The difference is the other proposed alternatives more directly suggest risk is involved.
It's a nice ESL example because technically, I don't think you're suggestion is wrong. In practice I think few would infer its implications.