First, so far this is just an idea. Zero development of the detection chemistry has been performed. But hey, at least they have already decided on their indicator color scheme!
Second, the concept requires that the antibodies, coloring agents and supporting chemicals come into direct bodily contact with (mucous) skin. That is very different from normal medicinal tests where you scrape off or otherwise obtain test material and then add additional chemicals far away from your body in a test tube. The FDA will look very, very closely at this and require lots of tests before it would grant approval. Lots of enormously expensive tests, far beyond what a novelty condom could ever earn.
So in summary - a creative but stupid idea.