I used the below MDM configuration payload based on the Apple developer documentation (https://developer.apple.com/documentation/devicemanagement/dock) and used Profile Manager to modify the keys.
The attached payload is working as expected. However, the issue arises when I try to restore the dock settings to their default on the managed devices; it isn't working. The configuration profiles are being removed, but the dock settings do not revert to the default. I tried the following methods but still had no luck. The situation is such that I had to use the dock payload mentioned above to make it usable.
rm ~/Library/Preferences/com.apple.dock.plist
rm ~/Library/Preferences/com.apple.dock.db
rm ~/Library/Preferences/com.apple.dock.extra.plist
rm ~/Library/Application\ Support/Dock/*.db
killall Dock
Please share your thoughts if you have come across such a situation.