Even if we find some brain structure somewhere using some sort of large-scale entanglement to do something, all that has proved is... the brain is using entanglement. So what? Even Penrose, someone who is definitely very intelligent, seems to have fallen at least a bit prey to the idea that showing that entanglement is in use is sufficient to demonstrate... something... about... something... maybe consciousness?
But even if you accept that entanglement is "spooky action at a distance", "spooky action at a distance" is an exceedingly large class of phenomena. And the dominant "null-hypothesis" guess that QM would yield at the moment is that it is a source of true randomness, which is not particularly different than the wide variety of classically-random effects the brain (and biology in general) is already working with.
Yes, it has not escaped my notice that if there is a such thing as a soul, that if it has some sort of non-physical existence, and if it can still impact the physical world through our body, that quantum collapse is definitely a place in our physics where there could be a reasonable mechanism for such influence to be exerted in a way that does not violate any physical laws but still allows for "external" information to be conveyed into the physical universe. But from where we stand scientifically, it is a long, long way to get to all of that. Huge, huge amounts of work to be done. The work might even be impossible. But it seems like a lot of people, even smart people, seem to think that chasm isn't there, and all we have to do is just establish "quantum", and we're done.
To put it another way, there is an exceedingly great chasm between someone saying "electricity!" and a modern computer, CPU, GPU, and all. Yeah. Modern computers use electricity. But just sending that fact to someone back in the 19th century would give them no useful information in building one. By contrast, give them information about how to build a transistor and maybe an example of a logic gate, and they'd be off to the races just the same as 20th century scientists and engineers were, even if they'd have farther to travel before they really understood the physics.
Maybe the brain "quantum"s... but how? What is different about the brain's quantum versus in-the-wild "quantum"? By what mechanism does organized information of any kind, from any source at all, emerge from the "quantum"? What kind of information can emerge? What kind can't? How is this information from "quantum" converted by the rest of the brain into anything useful? (That is, I'm not calling for anything as high as "human-visible changes in behavior"; I'll settle for any useful effect.)
From my perspective, that's just one step across a Grand Canyon-sized chasm. About all it does is fail to disprove that long chain of "ifs" above.
I'm not a secular humanist and I'm quite open to a wide variety of ideas... but scientifically, just showing "quantum" in the brain doesn't seem to carry anywhere near the amount of water a lot of people think it does.