A good response:
Academic debate on controversial topics is fine, but those topics need to have a basis in reality. I would not invite a creationist to a debate on campus for the same reason that I would not invite an alchemist, a flat-earther, an astrologer, a psychic, or a Holocaust revisionist. These ideas have no scientific support, and that is why they have all been discarded by credible scholars. Creationism is in the same category.
Instead of spending time on public debates, why aren’t members of your institute publishing their ideas in prominent peer-reviewed journals such as Science, Nature, or the Proceedings of the National Academy of Sciences? If you want to be taken seriously by scientists and scholars, this is where you need to publish. Academic publishing is an intellectual free market, where ideas that have credible empirical support are carefully and thoroughly explored. Nothing could possibly be more exciting and electrifying to biology than scientific disproof of evolutionary theory or scientific proof of the existence of a god. That would be Nobel Prize winning work, and it would be eagerly published by any of the prominent mainstream journals.
“Conspiracy” is the predictable response by Ben Stein and the frustrated creationists. But conspiracy theories are a joke, because science places a high premium on intellectual honesty and on new empirical studies that overturn previously established principles. Creationism doesn’t live up to these standards, so its proponents are relegated to the sidelines, publishing in books, blogs, websites, and obscure journals that don’t maintain scientific standards.
It is for these reasons that no intelligent person gives Creationism (aka Intelligent Design) any credence.