You can run padmin commands from the root shell (oem_setup_env) with the same ioscli. I find it easier to just be root and write my scripts using that path.
don't use oem_setup_env unless you need to, you are asking for a whole world of pain when it goes wrong.
and who wants a system with a broken vio server.
read the docs, if you cannot work it out as padmin call IBM.
if you don't have support - good luck.
if you do have support and they say use padmin and either help you find an answer or say there is no answer then at least you can get some help on a sunday evening when your vio goes down.
serously, there are too many unknowns using root on vios for things that are not documented as being supported.