Bazzite might not install printer-driver-brlaser by default. If you ran rpm-ostree install printer-driver-brlaser in a terminal what does it say? If you get an "already provided by" error than disregard this but, if it does install it then reboot.
That guide is definitely not going to work on Bazzite.
I'm on Fedora Silverblue and that package is installed by default. My printer (HL-2395DW) was automatically detected and required no configuration.