It's all possible to do, but the Guix developers do not provide assistance. From a purely technical perspective, software provided in binary form only impedes one of the main goals of Guix, 100% reproducible builds, because there is no source code.
If someone came along and offered a hardware-compatibility repo or redistribution, would the Guix community work with them, or would the relationship be more distant, or even adversarial?
I'm personally very interested in the project, and have no desire to poison the pure core of Guix, but I need my hardware to work.
But as a project following the Free System Distribution Guidelines (GNU FSDG) we will not recommend third-party channels providing proprietory software, nor would we want our project's communication channels (mailing list, IRC, etc) to be used to steer users to channels that provide non-free software.