It's a rather old rule to never split an infinitive . Nonetheless, it's still clung to by some.
Personally, I read "to not seek" and "not to seek" as the same. Sometimes I can "hear" a difference between asking someone not to do something and asking them to not-do, but it's often subtle.
I would advise you to try to avoid splitting the infinitive in your own writing (because you may be read by people who still hold that rule infallible), but not to worry about it when you read it elsewhere.
[a writer, not a teacher]
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