"C:\Program Files\Cakewalk\Shared Utilities\Internal" Cakewalk is aware of this as they are VSTs that are part of the internals of CbB and do not need to be included in the scan path. They are also quite frequently locked to Cakewalk Products.
The Sonitus plugins are all DX plugs and as such do not require scanning Cakewalk was historically a DX and DXi only product and did not support VST FX or instruments.
For years now, I believe ever since SONAR XL Cakewalk have had a file tree structure that kept the common aspects above the Program Directory. The Program directory held those bits unique to the release.
i.e. SONAR 8.5 Producer, SONAR X1 Producer, SONAR Platinum etc
Have you tried a Reset and Rescan in the Cakewalk Plugin Manger the VX-64 and associated files need to be in the
C:\Program Files\Cakewalk\Shared Utilities\Internal directory, before doing so.