In the kenopanishad bhashya, Shankara is simply referring to Uma, the teacher of the devas, as the wife of Isvara, ie, Shiva, who is sarvagna, ie, all knowing

This doesn't imply he considered either Shiva or Parvati as Brahman. Isvara is a given name for Shiva, which is accepted by all vaishnavas. The sahasranama also says, "Isvara uvAcha- srI rAma rAma rAmEti' . So shiva is known by the name of Isvara. It doesn't imply supremacy from a vaishnava perspective.

Sarvagna is based on pramAnas like "jnAnam icchet sankarAth", ie, shiva provides knowledge of vishnu. So he is celebrated as one who knows all the tattvas. Adi shankara used this term to show that Uma is the wife of the knowledgeable shiva and thus taught the devas.

Many rishis are also called sarvagna but that doesn't mean they are brahman. Shiva is called as sarvatma in the mahabharata in the context of his mind, ie intellect pervading everywhere, ie his knowledge is extended.

Shankara has not identified shiva as brahman there.

To those who accuse Omkara of being vaishnava, that is laughable. He is a staunch shaiva. But he is just quoting facts here. I mean, it would be ridiculous if I said appayya dikshitar was a vaishnava just because I have a prediliction for vaishnavism. Inclinations are one thing, but facts are another.

No more from me on this thread.