I get the feeling that on the other thread you said you were unable to change secure boot or uefi.
How did you use the media writer? Different computer?
Fedora 27 should boot as a hard drive order choice. When you boot to this usb, go directly to bios and see if the usb shows up as a hard drive.
You didn't really need to disable secure boot.
F27 properly made on a usb should boot to almost any combination of boot types, uefi, csm or what not.
See this for more tips.
https://fedoraproject.org/wiki/How_t...d_use_Live_USB
I just did a dd input the iso image and dumped to usb. Be careful on that command.