I am thinking that it is this that I needed to have instead if I wanted to only have users on levels 20, 80, and 90 to be voiced in the channel.
Code:
on @*:JOIN:#testing:{
  if ($ulevel == 20) { mode #testing +v $nick }
  elseif ($ulevel == 90) { mode #testing +v $nick }
  elseif ($ulevel == 80) { mode #testing +v $nick }
  else { halt }
}