Obviously we don't know *exactly* how their government worked but my guess is that *whichever* official representative makes a motion its on behalf of the planet they represent- and a motion is basically just to officially open something up for discussion meaning that even if 15% or whatever of other systems voted 'no' the systems either independently wanting military action and/or already under Palp's sway would have been enough to make the motion pass. Palps just needed someone stupid enough to have the balls to actually bring it up.

As for Siphodious (sp?) I feel it was just another case of too many names for too many superfluous characters and GL just lost track of it or it was meant to be someone else (like Dooku under a psuedonym as discussed elsewhere).