I'm all for the idea that consciousness requires more than a materialist explanation.
The scientist in me demands that "consciousness" have a different material definition--even before one attempts an explanation of anything.
One problem with tying consciousness entirely and only to the material brain is that the brain structures either differentiate developmentally to specific types of environmental targets--or they don't differentiate at all. Some are quite exotic: Hartline's limulus eyes in the horseshoe crab respond to a moving high contrast edge:
Lettvyn's "bug detector" in frogs:
1. Deny the eye visual stimulation, and the visual cortex dies. Worse, in the case of a monkey raised with eyes covered with bandages from birth, the eye ball had shrunk into the eye socket and fell out when the bandaging was removed.
2. Deny the eye appropriate visual stimulation during development, and the human visual system malfunctions. Deny social interaction and damage gets personal:
3. Cat's receptive fields tune to the visual world (according to many years of single cell recordings of cats by Hubel and Weisel):
we need to conclude that certain aspect of the world are part of "consciousness." Consciousness must include this real world information in coded form in order for the physical brain to function.