I disagree. If the purpose of the person's appearance was to teach writing (and why can't the regular teachers teach writing?), then introducing a disputed scientific topic produces no benefit for the school.
The writer is free to hawk her book at Wal-mart. Every major publication and media outlet presupposes "evolution," often at a "whale hopping on its tail" level of simplicity. Expanding the definition of "censorship" doesn't benefit anyone.
Disputed by whom?
I would put money on the table that if the subject was about "global warming" the author would have been welcomed with open arms.