That's exactly what's happening with those .dll's. More than likely it's because of your system performing a hang right at the time injection's necessary (not our fault), and unfortunately, there's not really anything that could remedy this except for trying a different injector. Try going to google, and typing "multi dll injector". I'm quite sure you'll find something that'll work eventually, just have to tinker a bit
Also, when using perx you DID remember to set the process name to Vindictus.exe right? (has to have a capital "V"
also, the reason that they're saying the injection process worked fine is because technically, it did. The error strings probably aren't capable of noticing a system hang during injection, since it's something below the software level. (my theory anyways.)
Also, post back with your complete system spec's please
Operating system, ram amount, and type, video card type, and processor type (I'm intrigued.)