I just wanted to say O M G revelation. thank you Justin

The thing with bend vibrato for me was. Well with normal vibrato, you start on a note, and bend up and back to the note, up and back to the note ... .to get vibrato effect
So when I came to try and figure out bend vibrato, I was trying to reach the pitch with the bend, then bend up and waver between pitch and above pitch. I just assumed it would be the same as unbent vibrato in that regard.
This is why I had so much trouble with it, and possibly why others are too ( You seemed a little confused as to why people thought it was so much harder ) now hitting pitch and letting it come down a bit and then back to pitch..... SOOOO much easier, sure its still going to take time to get right but its so much closer already. I feel a bit stupid really

But thank you so much for this lesson, it just had me stumped for ever.
With regards to the other two questions, I will let Justin give his advice, but have you tried using your index finger to bend the string above the one you are trying to get vibrato on. Do not pick the string, but use your index finger to bend it out of the way of the string you are working on with your ring and middle finger. I think its quite a common method to mute out strings when just normal bending as well, could be worth trying.