Do you have separate folders (64 bit/32 bit) for your VSTs? If not, you should have, you will need to sort your VSTs.
With the 32 bit and 64 bit VSTs in their own folders be sure when listing them in Reaper's VST 'path' preference to list the 32 bit folder, then the 64 bit folder (this is for 64 bit Reaper, reverse the order for 32 bit Reaper).
Good luck.