I don't believe there is currently an explanation based on known physical properties for how consciousness might be capable of existing on its own (without a brain).
Indeed. There doesn't even appear to be any plausible speculation. One wonders why it's even suggested...
My point is that there is a lot of general evidence that points to the possibility that consciousness can be separated from the body.
A lot of uncorroborated anecdotes, but nothing more - unless you know of some other evidence?
These experiences fall into the realm of a broader reality that can't be measured very easily with traditional means.
What do you mean by 'broader reality'? Reality is the sum of real things, anything else is not real, by definition. If this unattached consciousness can affect the physical brain, then it must be physical and real. If it's physical and real and can affect the brain's operation - the functional neurophysiology of which we understand well - then we should easily be able to detect/measure it or it's effects, because complex and subtle though the brain is, neuronal operation is well understood and well within the scope of our instruments. Odd then, that no external influence of this kind has been detected with the 'traditional means' that can so easily detect and measure neuronal function. I'm guessing, but you don't have the foggiest idea of what other means might detect this control mechanism, right?
In the case of the blind person - I suppose one somewhat implausible explanation for seeing things in a near death state is the subjects dreamt the activities going on around them. However, it doesn't seem likely that someone would dream something that actually transpired in this physical reality.
Well quite - if their brains were active enough to dream, they'd be active enough to perceive their environment, though not necessarily consciously aware of that. So, as an explanation, dreaming would be redundant as well as, as you say, somewhat implausible. My point was that anecdotal evidence without corroboration is no more reliable a guide to reality than my dream report.
It is possible the participants (the NDErs and those at the scene when the NDEs happened) conspired to construct these remarkable reports.
A conspiracy theory? That's almost facetiously implausible - surely it's more likely that the author faked the reports. But there's a far more plausible explanation - people have broadly similar internal (imaginary) experiences, because their brains and they way they are wired are broadly the same. Stimulate the brain in the right place (e.g. temporal lobe) and you'll get a similar experience to reported NDEs and OBEs. People are subject to broadly similar illusions, delusions, hallucinations, perceptual errors, memory distortions & failings, etc., etc. And you want to believe, on anecdotes alone, that these particular reports are different - unlike all others, they're real; there's no known or even hypothetical mechanism for how this could be possible, and no evidence to support it, but you want it to be real.
It seems to me you might make more progress by examining why you want consciousness independent of the brain to be a reality...