It almost come down to what x-ray and bakunin has said,
To add more,

Are you not seeing the SAN disks on VIO2 itself or on clients coming from VIO2?
If the answer is latter, I had a personal experience with VIO2, wherein the other SysAdmin just added the virtual fibre dynamically and forget to add it in profile. You may want to run a second pair of eyes over there.

If all is set and you can see those are connected and vfchosts defined, then it could be either faulty FC card or zoning issue.

As an sysadmin you can create virtual adapters and establish a connection between VIO and Client (using NPIV), but how the disk is presented to the system is the task of Storage Admin.

Its very simple, after you have provided WWN's of VIO, there is not much you can do (may be except for pulling the fibre cable from Fabric to Server).

Is error log showing any errors for FC card?