VRDB is a generic method, storing file parts that are often target of virus infections. So, it is capable of fixing even some brand new virus infections. However, it also means that it fails on some others
(that use special infection methods, for example). So, it's possible that VRDB doesn't work for this particular virus... (and I'm afraid Cleaner won't help either - it's a handy tool, but with a very limited set of supported malware, and Luder is not one of them).
What is rather strange is how the computer on the network could have been infected - when avast! detects the virus (for a few months now), it couldn't have been just executed on the computer. So, maybe there's an unprotected computer on the network which uses some open shares to open other machines' files?