Interesting theory by StarWarsExplained that maybe Gideon is trying to make himself force-sensitive. Might explain why he took the Darksaber. Perhaps he wishes to become the next Vader or Palpatine?
I find this a little bit strange though because why would artificial force-sensitivity create the mangled bodies in the tanks? A lot of people seem to think that the last shot shows some kind of battle-droids kinda like the Darktroopers from Legends, but I feel that some kind of genetically engineered stormtroopers makes more sense since they showed the lab in the same episode. Of course they don’t have to be directly related to each other, but that’s my guess anyhow.