The way I like to explain twin-linked weapons on Tau battlesuits goes kind of like this.
When gluing weapons to weapon hardpoints, they're two weapons.
When calculating point costs, they're one and a half weapons.
When firing, they're one weapon.
Hope that helps.
Although I do have to question your choice of a twin-linked flamer and a shield generator.
Anti-horde suicide squad?
Nix the shield generator, take a target lock instead. Save yourself fifteen points (suicide squads, which any Battlesuit squad that deepstrikes in close is going to be, need to be cheap) and allows them to each target a different unit, if a situation arises where it'd be useful for them to do so. And trust me, deep striking into flamer range is going to get them killed, shield generator or no.