Appreciate the time. I know the Shadow Splitter bot broke, so I thought perhaps the same change broke the Vanisher, but my memories of them being completely cloaked could indeed have stemmed from flying them in multiples.
If you say the unit IS cloaked, just doesn't look cloaked to the player, I found the same is true of the Seraphim ACU upgrade that
allows it to be cloaked in place when not moving (like a Selene scout). Maybe the same tweak could be made to that as well. (ESL0001 I believe)