That does seem strange - never heard of that before.
You could try reinstalling 1709 again as a repair install.
You can create install media from
https://www.microsoft.com/en-gb/software-download/windows10 but read the instructions as they differ for DVD and USB.
When you have created the install media, open Windows Explorer - This PC - insert the media and double click on its drive.
If using a DVD then that should start the process but if using an USB, that will open to the files where you would then double click on setup Application.
This doesn't affect your personal stuff or installed programs but correctly uninstall those programs first that you have gotten back.
Most programs have their own uninstaller which you should use rather than just using Windows Uninstall from Progs and Features as that tends to leave residue, which may have been the reason for the update resurrecting them - but that's just a guess.