set kern.vty=sc
boot
Maybe the console video is not kicking in.
Have you tried the old sc(4) to see if that is the issue? I have some boards that need it.
At the beastie screen pick #3 and drop to loader prompt. Then type:
set kern.vty=sc
boot
If it works you should see the FreeBSD installer menu.
To make it permanent you will need to add kern.vty=sc to /boot/loader.conf on your new install.
The vt(4) default console is newer but some machines have problems with it.
https://wiki.freebsd.org/Newcons