Follow the instructions for the other method by restoring the authorisation plugin file back into its place.
Install the TeamViewer app on another MacOS
Copy the "TeamViewerAuthPlugin.bundle" from "/Library/Security/SecurityAgentPlugins/TeamViewerAuthPlugin.bundle" to a USB. Make sure the USB is formatted in the native MacOS filesystem to avoid incompatibility issues in the next steps.
Restart your machine and hold Command+R to enter the MacOS Recovery mode until the Apple Logo appears. this process may take some time
Upon entering the recovery mode, you'll be instructed to select the language, username, and finally to enter your password.
After a few minutes, the macOS Utilities window will appear
From the list select Disk Utility
In the Disk Utility window, from the left pane select the "macOS" disk and in the right pane click on the "Mount" button. If asked, enter your login password. Now, the macOS disk is mounted. to verify this, look at the info bar on the page. it should be active and show detail information about the disk.
Close the Disk Utility window and from the menu bar, select Utilities and select Terminal
Once the Terminal window opened, connect the USB to the machine and type following: 
cp -r /Volumes/<your USB name>/TeamViewerAuthPlugin.bundle /Volumes/macOS/Library/Security/SecurityAgentPlugins/
10) To verify the above operation, enter the  following; it should show the "TeamViewerAuthPlugin.bundle".
ls -l /Volumes/macOS/Library/Security/SecurityAgentPlugins/
If not shown, try to retype step 9 but use the Tab key to autocomplete the path step by step. Do not hurry.
11) If successful, from Apple logo on the top left corner select Restart and wait for the machine to restart.
12) Now you should be able to successfully  login to your machine.

In case of any problem during step 9, especially receiving "Operation not permitted". enter the following:
csrutil disable
Restart the machine for the changes to take effect. Then, repeat step 3 and follow the instructions again. Once the macOS booted successfully, open a Terminal and reverse the setting by entering:
csrutil enable