The Skrull was watching the CEO very closely. The man was one of hundreds that were being watched by Skrulls. And now was the time.
It did not take long. The Skrull had been watching this CEO for a long time, even with his busy schedule of a Fortune 500 company. During the afternoon, the CEO would go into the spa to take a private time to de-stress. And it was during this time that the Skrull sneaked into the spar and hit the man over the head. After ensuring the body wouldn't be found, by teleporting the human to the mother ship, the Skrull changed shape. He became the CEO in a matter of seconds.
There were hundreds of Skrulls doing the same thing all across the country. Taking the place of certain humans. Some were in positions of power, like this CEO, and others who had political connections or financial connections.
It was the first step of the plan to conquer this world. And make it theirs.
And so far, it has gone successfully.