Libc6 cannot be updated as it stands. This is kind of a heavy dependency and changing it would throw everything into chaos. Technically, you could do it - but doing so would break everything.
This is a failing on the maintainer of the package that set a dependency without allowing for the proper backwards dependencies. Sometimes a developer has little choice to do this - but more often, they can just fine.
They just don't.
If you name the package, we may be able to find a workaround for you.
As I understand it, that script is only needed for Ubuntu 22.04 and up -or dereivatives based on 22.04 and up.
Zorin OS 16 is based on 20.04 - the script should be unneeded with the software working out of the box according to the GoXLR page:
Firstly, plug in your GoXLR and check to see if the audio devices have automatically appeared (generally by clicking on the Sound applet, or 'Audio' in your System Settings). If you see the GoXLR Devices (Chat, System, Music, et al.), you DO NOT need to use this script. You should be good to go with basic functionality.
If you are running one of the following distributions, and the devices don't show up automatically: