When you go to airport security, you have to show a boarding pass and ID with your name. However, doing so doesn't alert the airline that you are there. Also, you aren't required to show ID once you pass security.
It's quite possible to enter the airport with one boarding pass and have a separate pass with a completely different name on it. I would hazard to guess that he booked a flight under his name to Russia as a diversion while he actually boarded a flight under a different name to a different country.
There has been no confirmation that he was on the flight from HK to Russia, no confirmation that he is in the airport, and he never boarded his flight to Havana.
It's quite possible to enter the airport with one boarding pass and have a separate pass with a completely different name on it. I would hazard to guess that he booked a flight under his name to Russia as a diversion while he actually boarded a flight under a different name to a different country.
There has been no confirmation that he was on the flight from HK to Russia, no confirmation that he is in the airport, and he never boarded his flight to Havana.
I call smokescreen and diversion.