The real issue would be finding the creator of a DEX whose identity is anonymous on the Internet.
this is not our problem but its their problem . decentralized exchange are anonymous but that will be for the users of the exchange but for the founder they can choose to not become anonymous for future reference .
Can DEXs remain decentralized enough to go above the law?
sure they can . they didnt succeed of regulating etherdelta and the status of decentralize exchanges up to this point are the same decentralized but they dont go above the law . law are above all