Put a canopy over their stations and then mount the "minimap" displays over the canopy. If you're goal was to have the competitors also be visible to the audience.
As a matter of fact, you can also box off the sides with painted cardboard if you want to do that on the cheap also.
Think something along the lines of a baseball "dugout" for each competitor. Simple and should cost something like $100 at most to construct.
Its what most major gaming tournaments do but riot seemed to drop the ball on this one.
Sound proof booths. you see koreans do it all the time.
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