My suggestion is to try rEFInd when grub is being annoying. From Mint:
$ sudo apt-add-repository ppa:rodsmith/refind
$ sudo apt update
$ sudo apt install refind
and answer yes if it asks to install to the ESP.
Reboot and hopefully there will be a bunch of options, including Fedora ones with vmlinuz in the name - this should boot Fedora without using grub.
I wrote more here.