I am not a scientist, however the issue sounds facinating. What are the photons supposed to be entangled with exactly? If the photon was missing in earlier experiments, could it have been possibly hidden in the cavity you speak of?
I thought that photons moved at the speed of light and that a point could be shared by many photons of differing frequencies but not the same frequencies? Do not xrays pass through matter and thus briefly occupy the same points as other particles? I thought actual teleportation was impossible, but did think that something similar could be accompished: the movement of an object which is kept fully intact and moved whole at the speed of light to another location, and encapsulated withing specific fields of wavelengths to enable what is contained to pass through solid objects without damage. What are those things that are so hard to sense because they pass through virtually anything, like one in the end of a pi actually strike an object and is able to be detected? That would be a good encapulating wave field. Intresting stuff, if only I could digest and comprehend it! :)