Can "but also" be split in "not only ... but also"?

I think I generally agree with the statement

When using not only . . . but also in a sentence, parallelism should be the goal. It means that the words following both parts of this correlative conjunction (i.e., not only and but also) should belong to the same parts of speech.

https://www.grammarly.com/blog/parallelism-with-not-only-but-also/

However, the Cambridge dictionary has an example that is not 100% parallel in my eyes, as "but also" is split:

Not only did she forget my birthday, but she also didn’t even apologise for forgetting it.

https://dictionary.cambridge.org/grammar/british-grammar/not-only-but-also

What I would expect, with maximum parallelism, is

Not only did she forget my birthday, but also she didn’t even apologise for forgetting it.

Is my expectation wrong? Is my formulation acceptable?