I've been reading a lot of things about Tantra, and they say Consort Practice is required at least once to attain enlightenment outside of the Bardo.
So, how did Shakyamuni attain enlightenment? He didn't have a consort under the Bodhi Tree with him.
"All memories and thoughts are the union of emptiness and knowing, the Mind.
Without attachment, self-liberating, like a snake in a knot.
Through the qualities of meditating in that way,
Mental obscurations are purified and the dharmakaya is attained."
-Ra Lotsawa, All-pervading Melodious Drumbeats
"You must experience that the various thoughts, in whatever form they arise, are an empty appearance and not a definable entity."
-Clarifying the Natural State pg. 33