Have you tried any of the online escape room games by Masters of Mystery?
They offer an Alien Themed/Time Travel Escape Room Game called Ceres Mission. This one time play game takes around a hour to play.

Online Escape Room Plot
In exactly 60 mins the “Ceres Asteroid” will start entering our atmosphere. Once inside, its impact will cause hundreds of millions of deaths.
As you know, throughout history, Extraterrestrial beings have helped us develop our technology and thanks to them, we can now time travel. Our organization has managed to keep this technology safe and from falling into the wrong hands.
These beings have come to help us once again. They have the technology to deviate the asteroid and keep it from hitting our planet, but I’m afraid they have been intercepted. We do not know who is responsible, but we have a lead…
Use the time travel machine to fix this. The future is in your hands.
Time To Escape: 1 Hour
Age: 13+