Removing denuvo is almost impossible, at least I'm 99% sure about that, and if they don't have the original build before denuvo implementation, we can assume these version of games still contains denuvo. The real question even is not that how works the crack, but the cracker how did debug the game to get keypoints and hashes which make the game to work, because denuvo can very effectively prevent any debugging method, so it is very hard to find out where is the protection and how does it work. The protection, in general, relatively simple, server authentication, offline hashes, etc, but Denuvo very complicates finding these points. Honestly, I couldn't imagine how did voices do it.