Not sure if this will help or if this is the reason for the problem you’re facing, but “technically” OBDC driver versions of the 18.x variety are not supported yet. The most recent versions we support right now are of the 17.x family.
@dmccalla so you think a viable recommendation would be to downgrade to v17 (we have exported registry keys and C:\Windows\System32\msodbcsql17.dll still exists in server) and then try the upgrade again? Thanks