PowerPath without a license supports one HBA only.   Did you "claim" VNX devices (configure the string) ? I believe it's explain in "Host Connectivity Guide for Windows"
I have installed MPIO on a windows 2012 server however I am still seeing all of the LUNs presented to this host from my VNX on each path I was expecting once the MPIO was installed I would only see the LUNs listed once under disk manager.  Are there special steps required to setup MPIO using MS SW ?  There is mention of certain vendors may provide their own DSM configs is there a DMS package needed from EMC.  Also if I just install PowerPath 5.7 is this free but only providing failover for the host?  thanks
Windows 2012 MPIO setup