Having looked at the Vizio5.1 system my self, and specifically looked at the satellite speakers, I would definitely say yes. These stands offer a few different options for the mounting of speakers. The support from Atlantic is very good.
I don't know but the adapter that comes with these stands is very 'adaptable'. You will see what I mean if you get them. Basically my current speakers which are Panasonic, lie on a small pedestal with a screw that attaches to the back of them and fits inside a metal loop that is like 8 inches high. Basically, your speakers would need to be insanely shaped to not fit. So no, there is no 'exact' fixed bracket or connection. They are designed to fit nearly all satellite speakers.
Not sure about your particular system, but mine came with padded tape mount also to make it somewhat universal. That's what I used. They have never wobbled or leaned. Super sturdy. 3 kids and 3 dogs no problem. I would NOT suggest unmounting though. I can't imagine finding that strong of tape anywhere. I've tried for other purposes.store bought is not the same.
I'm not sure of what your question pertains to but the speakers & the speaker stands are two different things.....the speakers are the audio producing devices while the speaker stands are devices for mounting the speakers on (usually the rear speakers), rather than mounting the speakers to a wall or ceiling. they can be positioned anywhere one would choose for best sound quality or for convenience (as for putting them at ear level).