I could see a "scaly-skin condition" Croc a la Azarello/Bermejo happening, but the full-on reptilian look? No way. Especially if WB/DC wants to steer clear of comparisons to Marvel, since one of their franchises has already yielded a reptile-man.
On the flip side of that, though, part of me kind of wishes Goyer had had the wit to give one of the Nolan Batvillains a pet crocodile named Waylon.
"My folks came to the U.S. as immigrants, aliens, and became citizens. I was born in Boston, a citizen, went to Hollywood and became an alien."