Hi Josh,
The bit-ness is a requirement according to MS TechNet articles released with the VDI plugin. However, that does not seem to be indicated as necessary when using PCoIP as indicated in this guide: http://www.vmware.com/files/pdf/techpaper/vmware-horizon-view-microsoft-lync-install-configure.pdf
If I am reading it correctly, essisim's configuration should be covered.
However, I am wondering if there are any ports that need to be opened between the client pc and security server before it hits the Lync 2013 server.
Any ideas?