2.9.5 should not be available to download due to it being broken.

I think you need a preferences file to pin the linuxcnc repo files in /etc/apt/preferences.d that looks something like
github.com/LinuxCNC/linuxcnc-live-build/...c-uspace.pref.chroot

The post I put earlier was from trying to install the package manually, by
Trying to install from the Linuxcnc repos would break the build. And to be honest I think the Release may only reference the doc files. I'd have to check my notes for sure on that one. I may be wrong but I remember having a look through it.