Plenty of people turn from Christianity to paganism, it's actually a popular way for edgy Christian kids to rebel, particularly in the American south where there's a particular stigma against "devil stuff." I know a few such people, and I've never heard of anyone having to do any rituals to "renounce" their faith, nor have I ever heard of the "peace sign as broken cross" being used as a symbol in any ritual.

But then, as you doubt sources from Wiccans, so I don't know what else to tell you. These religions aren't hiding anything, there's an entire section of pagan and neopagan books at any bookstore, you can do research online, or probably find some pagans near you and talk to them. They'll tell you the same thing I'm telling you.

In fact, I'll help you out... start here: http://witchvox.com/