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[MadMojoMonkey]

Alice tests for the y spin, therefore Bob can't test for the x spin, why's that? Bob, in his bubble can test for the X, Alice in her's can test for the Y. Bob still doesn't know the Y, nor Alice the X as they're separated.

This isn't so much an EPR question as it is general weirdness with measuring 2 properties which are related via Fourier transform.
Components of spin are similar to position and momentum.

To be fair, Alice and Bob can test for whatever they want. They just don't expect to have correlated results except under special circumstances.

Alice measures along the x-axis. This make 0 predictions about what Bob might measure along the y-axis or z-axis. All Alice knows is that if Bob measures the entangled partner of the particle she measured, then that pair will exhibit the conservation laws which conserve certain properties (mass-energy, angular momentum, etc.). Assuming the particles originated from a system with 0 angular momentum, then if Alice measures her particle as "up" along the x-axis, then she knows that Bob will measure that particle's entangled partner as "down" IF he measures along the x-axis.

To the extent that his measurement is not 100% perfectly perpendicular to her x-axis, he will see the correlation associated with the "shadow" of that misalignment on the x-axis. I hope you are familiar with the vector multiplication operation called the "dot product" or "inner product". For any 2 vectors, the dot product tells the magnitude that one vector shares the direction of another vector.

The inverse is also true. Assuming Bob and Alice have their detectors set up an a perfect right angle, then neither can make any predictions about the other's measurements. However, if their detectors are not perfectly perpendicular, then they can BOTH make predictions about how much correlation there will be between their measurements and the other's.

He even says as much a few bits later, "The two particles are somehow communicating to one another instantaneously, but this violates special relativity." So how are Bob and Alice assuredly pulling this feat?

I'm a bit lost on this question.

I hate to repeat what someone else said without further understanding, but -
"It could be that entanglement is observation."

The source of that statement was an angry (but intelligent) man who felt like the various interpretations of QM are a conspiracy of lies. There is much reason to doubt his claims.

On the face of it, though, that's my kind of statement.
Two particles interact. That's observation.

Any time when Bob and Alice meet together to share notes, who's to say what the X/Y spins are then?

???
Bob and Alice are comparing notes about their observations - and you're asking who's doing the talking?
They are both "to say" what they observed.

No experiment can simultaneously measure the spin along more than one axis. Each of them can say what they measured on any given experiment. They can predict what the expected value of the correlation in the data is based on the alignment of their measuring devices. OR they can predict the angle of discrepancy of their detectors based on the correlation of their data.