The perception occurred accurately for the creationist, but then the opinions based on that perception had to be woven into a strange hypothesis in an attempt to circumvent the obvious contradiction between the fact (the perceived fossil) and the mental model of creationism in the perceiver's head.

A person has to be pretty far gone when they have automatized evading perceptual evidence to such a degree that they are no longer able to be consciously aware of the contradiction between their beliefs and what they perceive. This kind of evasion can be seen in cults, extreme religious groups, extreme political groups, where extreme = evading perceptual evidence that disproves your held beliefs. Usually group pressure is involved to automatize the evasion.

Perception (and I've been using it in the strictly integrated sensation sense) is our link to reality that enables us to make sure that our mental models don't fall off the deep end. Evade perception at your own peril.