It's sort of a moot point in this case, isn't it??? The Deputy is supposed to be someone the company can go to to report problems or abuses from within the company, who can deal with the AEA offices anonymously without fear of repercussion from management. With most of your acting company BEING management, it's not an issue - management will know who the deputy is, and they'll know firsthand what (and who) the problems are... so electing someone as deputy in this case is a formality.
This is, obviously, not the typical situation, and can lead to some very interesting, and perhaps sticky, moments... but I would think the only ones who could NOT serve as deputy would be any who are signatories on the contracts... but what difference will it make in the long run?
Art