Plot holes aren't usually so literal.
That's the mouth of a miles-long tunnel under the Midland Circle building. The Hand dug it smack dab in the middle of Manhattan in order to connect our world to a weird kung fu dimension with giant f*****g dragons in it. In the process, the Hand kidnapped and/or killed scores of people, attacked a hospital, orchestrated a citywide media blackout, seized complete control of the city's underworld, and infiltrated several of the biggest and most influential corporations on the planet, like Rand Enterprises. All of this right in the MCU heroes' backyard.
Danny Rand and his struggle to gain control of Rand Industries received a ton of media attention, so fellow rich d******d Tony Stark must be aware of the guy. Both Luke Cage and Daredevil have attracted multiple headlines in New York newspapers detailing their vigilante escapades, which makes them globally known figures almost by default. Hell, even the Punisher's rampage and consequent capture and trial in Daredevil Season 2 would have made at least national news. It's nearly impossible that a certain team of superhuman protectors of the planet wouldn't have noticed that something's going on in the Big Apple.
Tony's news alerts are only set for shawarma resturant openings.