Man, people that were influenced by ISIS managed to somehow escape it and, even though they say they are there for The Islamic State, they kept drinking beer, alcohol and even getting drunk. That is something Quran forbids. Therefore, they are not truly worshiping Islam, but something else. Because if literally somebody would kill for Islam, they would respect each and every thing Quran tells you to do. But still, Quran forbids killing, so... They are not worshiping Islam. It may be that they are worshiping devil, or that the big regions such as Russia or USA are in play.