So, I have two very close tidally locked planets, each fills up about 2/3 of the sky of the other. They both have about .75g of gravity. There is also a moon orbiting the two planets at some distance (where it is stable). One planet is predominantly ocean with scattered topical islands, small forested islands, and some swamps. The other is mostly desert, in that it has little water.
Note - Assume these aliens have interstellar travel, and are able to travel just under the speed of light. If you think they'd have other kinds of technology as well, then feel free to include it. These alien races would like to help the planets come together gently, let them help if you can. (They can't stop the planets from colliding.)
Now, is there a way for the two planets to collide and not wipe out each other?
You can change some factors about the planets, but their sizes must be between Mars's and Earth's. As a last resort, the inhabitants can flee the planets, but I want to avoid this if possible.