I think the problem is defining "distilled". some call reverse osmossis distilled water.
I dont see how "steam distilled" water could possibly contain any fluoride. the fluoride would have to be bound to the OH bonds and stay bound through two phase changes - once from water to steam, and then again from steam back to water. this seems highly unlikely to me.
however, there may be other non-steam distillation processes that do not remove fluoride.