If the detection of certain types of reality defines it, then detection of matter as a particle spawned from an anti-annihilation would instantly infer antimatter as its partner in the pair. Bell's experiments seem to confirm this instant action, but perhaps the confirmation of the action only takes place when the researchers communicate, which is not instant. Effectively the two researchers, or more specifically their information about the state of reality, are in a quantum flux relative to each other and only set as certain when they communicate with each other.
Here is a postulation; that if the communication between researchers was not possible, it might be that two particles could both be matter, or both antimatter, based on probability at the point of their detection.
Would it be possible to design an experiment where a quantum state of an entangled particle could be logged locally yet remain unknowable by its partner, thus giving the particles freedom to break symmetry?