the main problem is Freebox is not designed to use with keyboard at all (other it have some shortcuts to various features, but is never meant to been use with keyboard only, but more function like a remote controller), but is mostly mouse driving software. A mouse is also cheap to replacement, if it got broken and you doesn't not need to have a good mouse, just it works.
You can't exit in freebox and most other "party" mode software with the mouse only, but costumers can normally easily breakout and exit with a full keyboard and close down Freebox (and other software as well), if you are not aware to hide these system keyboard keys, so hence I can't really re-commered keyboard, due with this problem.
That really why none at BYOAC is really want to use a keyboard with a jukebox application (ETC it why BYOAC got its name). These software in this forum is really meant to been used without keyboard, but used with various forum for others controllers.
If you can use joystick and buttons, there exists some arcade jukebox software out here (including my own), there is also software to use a keypad style. Keyboard is not a options by folks in this forum, but nearly all other form for controls.
You also need a commercial Freebox license with is something higher than in home use (I understand completely that, no negative, Barcrest). Here I cant help, since I is not the author behind the app (but I have behind of a other jukebox application, MultiFE (before it was MultiJuke) which operate with mouse, joystick, keyboard or touchscreen.