For me, it would be an amazing story twist. People might think Hammond was a good character simply because he’s a cute looking hamster.
Take some movies for an example:
The Good Dinosaur (Disney Pixar), the audience might have thought T-rexes were bad characters simply because they were ruthless, meat-eating predators. Instead, they were actually good and helpful to the main characters. Personally, it’s really awesome that Pixar made them good as T-rexes were mostly portrayed negatively.
Zootopia (Disney), Bellwether appeared to be sweet, innocent-looking sheep but she’s the main antagonist. Foxes were commonly depicted as cunning tricksters, especially in Aesop’s fables. Nick Wilde decided to be a con-artist because of his troubled past, but he was sympathetic towards those who experience prejudice, again because of his past.
Back to Hammond, he seems ignored the chaotic surroundings. The gorillas were rampaging in the background while he continued building his things in his story trailer.
What if Hammond was responsible for causing the uprising? Without the humans’ interference, Hammond could escape, free roam around the Moonbase and do whatever he intends to. Unlike Winston, Winston decided to escape from Lunar Colony as he never wanted to be part of this riot.
In Junkertown, Hammond had a lot of fun with mech battles. This means he might actually enjoy the violence a lot.
Based on one of Hammond’s sprays, Hammond and Winston were friends when little, but things could change as the time went by.
If Winston and Hammond were truly friends, Winston would have brought Hammond along, built a makeshift rocket and escaped to the Earth together. Instead, Winston built it by himself and Hammond secretly followed Winston because he sensed the opportunity.
Sigma was released as an evil Tank, but the fact is that he was being used instead of joining Talon willingly. Just like Widowmaker, she’s brainwashed by Talon and became their agent carrying out assassinations.