Quick update- making a bit of progress on this (I think).
One thing I noticed was that the ntprint.inf file was referencing ntprint.inf_x86... for the active driver reference on the problematic machine, ntprint.inf_x64... on a working machine
I did the following and so far printing is back to normal for Type-4 drivers-
1- ran "pnputil /enum-drivers" from a command prompt
2- used psexec to elevate and run regedit as system
3- investigated the - HKEY_LOCAL_MACHINE\DRIVERS\DriverDatabase\DriverInfFiles\ntprint.inf
4- updated the (Default) value to include - ntprint.inf_x86_6fbb4b09e9354bf2 and ntprint.inf_amd64_6fbb4b09e9354bf2
5- updated the Active value to - ntprint.inf_amd64_6fbb4b09e9354bf2
Note- the exact values of ntprint.inf_x86 and _64 might be specific to build or updates installed, I'm not sure that they are universal to 2016. I used the values that existed in the DriverStore - C:\Windows\System32\DriverStore\FileRepository on my servers.
Not sure if this fix will do the trick long term, but so far after scrubbing out old printers, drivers, and pretty much cleaning out all registry / driver on the server its the only thing that has looked promising. Hopefully this will help point someone else in the right direction.