The answer lies in the creation scientists' claim that the Bible is 'literally true'. So it is really a debate about the interpretation of Scripture, it is really a theological debate, not a scientific one. In the four Gospels of the Bible there are materially irreconcilable accounts of where Jesus what, what he did and said during certain events. Taken as material fact in the way the creation scientists claim, the Bible therefore contradicts itself. But taken as stories, fables or parables, used to make theological points, there is no problem.
Evolution provides such an account.
This is a purely scientific issue. Both objections can be answered. Certainly there are some missing links between species in the fossil record. But their low number can be explained if the process of differentiation into distinct species takes place on time scales short compared to the typical lifetime of a species, so that evolution proceeds in short bursts and intermediate forms would only be available to go into the fossil record for a relatively short time. This idea is called 'punctuated equilibrium' and is looking ever better as we begin to learn by computer modelling how new mutations can lead to bifurcation of species in only a few generations.