The BK are meant to be training up some young Sisters to take over from Gulzar right now. No official comment as usual.
In the early days, yes, there were more than one medium. Allegedly 'the spook' using more than one at once in one case. There were also a lot more strong or profound trance/possession like states from children going into trance for a week, plenty of "visions of heaven" to women screaming and howling.
Some BK Brothers have one off incidental visions. I knew of a Western BK that had a "vision of heaven" as he described it ... he left Gyan later.
Then there is the visions/out of the body "journeys to the Subtle Regions". Many Sisters seem to report them. Sometimes they are similar but more often they all come out a little different. The BKWSU put a damper on Sisters doing those independently, perhaps we might discuss why.