Zorin 17.3 Pro Upgrade (From 16.3 Pro) Borked

Because You ahve AMD Graphics the Driver for it is already in the Kernel. So, You don't have to install one like You would when using a Nvidia Graphics.

Because it is in the Kernel, You could try it with a newer one. If You want to try it, here is a Manual:

But to say that: Install a different Kernel can cause Issues. So, be careful. From the Manual, I would suggest to take the Mainline Option because You get a graphical Interface to install a Kernel.