It's the list of VST(i)s that Reaper has scanned - in your AppData folder (click [Options] >> "Show Reaper resources...". If they were scanned OK you'll see the 4 entries in the file.
I've just looked here and all four are scanned OK But they all show up in the FX Browser with the same name; so I right-clicked each one in the FX Browser and renamed it:
Note: I have not changed the dll names.
[The same goes goes for Absynth 4 and other NI products with FX versions.]