Don't have a definitive answer, but when I have included a GOL flight on a UA ticket, the UA web site provided the record locator. However, when going to the GOL web site the response was always contact the reservation center. Never bothered to do that. So even if you get the information, you may always need to call. The only Brazilian airline it would work with was JJ, as JJ used to be in Star Alliance and the system connectivity must have remained when they left. Even with Azul, which UA has an 8 percent stake in, it works like with GOL.