In OM Lx dnfdragora or Discover do not have capability to do a distribution upgrade so that was never going to work. Can not use them to upgrade from one OM Lx version to another.
Problems like “My dnf is broken” usually involve a GUI package manager being used.
Notice any difference between your list and my list? This might work >>>I would start with going to main/release repository and download .rpm’s for dnf, python-dnf, dnf-conf, dnf-yum, dnf-automatic, and lib64dnf2 and try to install them with rpm. If rpm complains of any other dependency then download those and add them to the list until you can get them all to install without error.
To make installing those easier create a folder (say RPMS) and download all the .rpm’s to that folder then open Konsole and cd to that folder and install them with one command:
$ mkdir RPMS
then download the .rpm’s to this folder and:
$ cd RPMS
$ sudo rpm -Uhv *.rpm
If the result is an error about a missing dependency then download that package and add it to the list and keep on until the command is successful without any error.
Or you can do a fresh install of OM Lx 4.1 > this might be easier.