I had someone ask me today if they plant a fig tree near a black walnut tree, would it die. In other words, would the juglone from the walnut tree kill the fig tree? I honestly don't know. My thought is that since the fig tree is not a native species or competitor, it may not affect the fig tree. I know mulberry trees (same family) are unaffected by the juglone. Can anyone confirm this who may have this growing scenario? Thanks.

I don't see any reason why ficus would be resistant to juglone.  The problem is that it makes metabolizing via root very difficult.  Birch has specific adaptive resistance to it.  I don't know that figs lack that resistance, but it seems really really improbable. 

I believe they will have resistance to juglone for the reasons I stated in the initial post. They are not a native competitor to black walnut trees and mulberry trees (in the same family) ARE resistant. I know this from empirical proof. Anyone else have a thought? Thanks.

A few years ago I planted 3 fig trees in my back yard in close proximity to numerous black walnut trees.
one has died.
one, was stunted badly, and  since it was a variety i wanted to keep, i moved it, and it is since doing much better, putting on healthy growth.
another is still back among the walnuts, not doing terribly well, but still alive. it is not a favorite so I am leaving it there to see.
My plants in pots away from the walnuts are growing much better than the one in ground near the walnuts. My other in-ground fig is very far from the walnut trees and both last year and this has put one 2 or more feet of new growth per trunk, and multiple branches.
As you note, figs are not a native competitor to black walnut trees..... so there  would be no reason, no benefit, for figs to develop a resistance to juglone. Mulberries are a native competitor so it is to their advantage to have resistance.

Not being a native competitor to black walnut isn't really a contributing factor.  Organisms don't make genetic plans or have local genetic information for instance.

Being related to mulberry trees could be something though.  Perhaps an experiment ought to be in order?