For example: the original Jurassic Park's end credits suite concluded with the creepy 4-note leitmotif and a spooky high-pitched string chord ... but that was an acceptable way to wrap up the End Credits because that movie's ending was NOT a happy ending.
All three "Park" movies had deaths of heroes' friends and/or loved ones. The most positive thing about the ends of 1st and 3rd movie is the heroes being relieved to have escaped. So it's logical to end the credits suites for both of those movies with music that reminds the listener of the horror that those islands provide.
The 2nd "Park" movie's credits suite ends on a powerfully borderline-bombastic and adventurous tone, because that movie was mostly about going on a "heroic" journey with the established purpose of saving the dinosaurs from human interference, and the movie ends with Hammond apparently succeeding in his activism.

Honestly, in my view, a bombastic and/or heroic tone similar to "The Lost World"s end credits suite would've been more fitting for Dominion's end credits conclusion instead of the sad/sorrowful tone Giacchino went with.