Spoilers.

My critique held much of what yours was in that it was easy to telegraph, but even without that obvious turn it just rings hollow. The story didn’t really need a villain IMO, considering the potential extinction of the entire human race is about as menacing as you can possibly get. We don’t really need the Company Man sabotaging the Hero anymore, do we? It’s such an a played and annoying trope that needs to die. Armageddon had it with Fitchner’s character, ID4 had it with Rehborn’s character, and now we got Matt Damon playing that generic role. I love surprise cameo’s and have no beef with Damon’s presence, but *that* character needs to go.

It’s a lazy way to generate tension IMO. He written just fine until the heel turn. It would have had far greater emotional impact, for instance, for them to discover that he’d lied in order to be rescued, resulting in a group debate on whether to rescue him or leave him stranded based on his selfish actions. We’d see a true test of humanity, of making a hard choice, of three scientists being faced with the task of being judge, jury, and executioner for a guy who put the entire human race at risk for his selfishness. By having him ultimately become just another generic “guy who attacks central character and sabotages the mission”.

If you need a device to split everyone up, then brainstorm that next piece. It shouldn’t have been hard considering the fuel issue. You don’t need the weight of Coop tricking Amelia because we’ve already experienced a significant emotional moment just prior to this point in the story, and so leaving her to head to the remaining planet alone to enact Plan B while Coop tries to salvage Plan A still makes sense and holds emotional weight.