Let me get this straight - you want a wireless connection between your pre-amp and powered speakers? Is that what you want? And do the speakers have bluetooth? Could you indicate the brand/type?

I didn't understand 100% what you want exactly, but NO, don't do it.
The unit only supports 1 input that is sent to 2 headphones (or speakers). (Same signal, so not split left/right or anything).
Connecting with headphones is a matter of luck, it can easily take 2 minutes. With a loudspeaker you don't want that.
Sometimes (almost every time) one of the headphones starts to drift in the middle of the film, so the sound shifts in relation to the picture. Sometimes this happens even when only 1 headphone is connected.
Unfortunately, I don't know of a clever alternative, sorry.

Yes, it should work. But why do you want one with TWIN? You probably only need 1x stereo sound to transmit. Or are the cinch cables only mono? Then yes