There are older challenge caches based on this, such as GC38HGQ. But as pink unicorn pointed out, they are no longer allowed under the new challenge cache rules, and there is no practical way to build a checker on this criterion.
And, really, thank goodness. There are enough people doing fake discoveries based on the TB photo gallery and using scripts to "discover" coins and TBs they've never seen. (I can only guess they're trying to inflate their badge score or something.) Basing a challenge cache on this would make it even worse.