We know that people sometimes put 'had' in front of past tense verbs and we know that when they try to put 'had' in front of an irregular past tense verb, 'had took' doesn't sound right so they use 'had taken' instead of 'took'. It's called 'forcing the iregular past participle'.
Why else did Sparks write what he did?
If anyone has a better explanation, let's hear it.