This type of Guillo are Guillos on post apocalyptic old earth who adopted western cowboy culture, and dress as such, with huge hats that cover their ears, providing them shade from the hot sun (why they didn't develop pigments like island Guillos) and protecting their ears from the guns and dynamite they grew to love so much, they have strong southern accents that were likely fake at first, but over time through generations it just became how they talk.
Guillos of this faction literally call themselves "the yeehaws" and they make their homes in old western towns.
Guillos got to earth in a few ways, the first being that they arrived on Basfliman slave ships that went to earth, and escaped their captors.
The second way was the event of 2023, which was almost 1000 years in the past at the events of which my universe takes place, because when the ball dropped it turned out to be filled with a whole Guilliguine village, this event was caused by the Godesss of madness.