On The Orville Season 2 Episode 14, the repercussions of Grayson's decision have disastrous effects on the crew of the Orville, the Planetary Union, and the whole galaxy.
After Grayson's decision to decline a second date with Mercer, seven years elapse and the Kaylon attack on Earth is successful, destroying most of the galaxy and wiping out all biological life. Mercer and Malloy have a shuttle and manage to steal a food synthesizer from a remote Union listening post and escape Kaylons before a scavenger freighter picks them up. On board the freighter are Grayson, LaMarr, Finn, and Keyali. Grayson explains what has happened to the timeline, that the mindwipe didn't work and she changed the events. Getting supplies from a resistance cell headed by Alara Kitan, they plan to send Finn back to fix the mindwipe and thus fix the timeline.
In order for the plan to work, they need to raise the Orville from the depths of the ocean on Earth. When they find the ship, they find Bortus living there. They raise the ship, access the information they need through a deactivated Kaylon soldier, and set up the equipment to send Finn back. Mercer and Grayson affirm their feelings for each other.
In her apartment, seven years ago, Grayson wakes up, gets zapped into the future only to reappear seconds before Finn appears as well. The second mind-wipe works and when Mercer calls for a second date, Grayson accepts.
On The Orville Season 2 Episode 14, the crew must figure out how to contend with the disastrous fallout from Kelly's decision during the season 2 finale.