I wont entirely place my bet on Kyrie being Beatrice but its possible that she was involved.
And its best not to mention episode 5 stuff here.
The only thing im concerned about is that particular event in episode 1.
Rudolph said he was going to die to both Kyrie and Battler and Kyrie went up to question him, in the absence of Battler of course.
Well, i presume Rudolph would have told Kyrie the reason and being as intelligent as usual, i cant think of any reason why the two of them cant plot together to try to solve whatever problems Rudolph had.
Heh, in terms of capabilities, i think that the Rudolph and Kyrie pair is ranked above the other pairs. Both in wits and strength.
The weird thing is that, even though Rudolph knew he was going to die and possibly with Kyrie's help, the two still ended up dead.
I can only think of two possible scenarios:
-Kyrie and Rudolph was not sufficient to counter whatever that happened during that night.
-Or... It was on purpose.
I can't really imagine the contents of the adult discussion that managed to give Rudolph an impression of his impending death. The only way possible for him to do so would be to get some clues and hints of the happenings. Say maybe seeing a servant hide a gun in the toilet or maybe having Eva personally threaten him.
However, the consistency of Rudolph's death at the first twilight seem to favour the latter possibility.