So all the info I see tells me how it is guaranteed from illustrious and above, but what I can't seem to find is this: is their a chance of getting a wisp off evenstoning a random piece of high level gear or ONLY obtainable from illustrious+?
I'll give a shoutout to a player named Aired. His youtube channel explains everything in depth and they come with spreadsheets if you really want to get into it.