I tend to agree that a Theravada forum is not the best place for this discussion. In fact a lot of this could be copied over to Dharma Wheel which our hosts here have also kindly created and there may also be more participants interested in this sort of thing. (( Edit: having had a look, maybe Dharma Wheel is not the place, it kind of stinks of enlightenment over there, while at ZFI we kind of meander aimlessly in samsara. It's a tough choice...
As for whether what Dexing is presenting is accurate or not, it's worth keeping in mind that Mahayana is a term describing a bunch of schools with lots of common ground but often differing interpretations of certain notions (for instance some scholars believe that Madhyamaka and Yogacara are contradictory while others see them as complimentary). I am not qualified to pronounce judgment one way or another but I do recall reading a similar interpretation of emptiness as taught by the Yogacara school elsewhere so it may actually be pretty standard. I am also guessing that where it diverges Ven Huifeng would correct it, like he did in the identification of space and emptiness, color and form, which is perhaps sloppy but probably doesn't go to the heart of the argument.
But in the end it boils down to semantics and realization I guess. Semantics in the sense that people could mean the same thing but be wording it very differently. Realization because until then, it's all just words and pretty ideas.
And even great ideas in the absence of appropriate preparation can cause harm rather than liberation.