Sure, he could but he really does not care about that role. Perhaps because he stepped into the role of 'outsider' with a made-up mind rather than an open-mind? Outsiders can be good but if their contribution is little more than rethoric then their contribution is just 'noise'.
Art: If he is right, then hopefully, the self-corrective nature of science will kick in at some point
and realign us. If he is wrong, then his focusing attention on the
weaknesses of evolutionary theory can only help those practitioners who
care about evolutionary theory to tighten up their model. So, bring on the
Philip Johnsons. The only people who have anything to fear are those with
a vested interest in evolutionary theory as a world view. In that case,
Johnson is attacking your religion, and that is another issue altogether.
I'd rather have them bring on people who are willing to not just make the empty rethorical claims but who is actually willing to defend them and understand the issues. Philip Johnson has contributed little to the cause of science.