How can I get rid of the "watchbog" process?
One of the best things about Linux is that you can only re-deploy it for free. I suggest you delete your operating system and reinstall it. Problems to shoot the virus is almost always a useless exercise in my experience. Therefore, backing up the files and reinstalling them is a good return on investment.
If you really want to get rid of the process without reinstalling it, start with a "localization" for it. It runs as ./ so it's very likely to be local somewhere in the file system. Most likely you have a brother process that will reinstall it if you delete it, but I would start by looking for the location of ./watchbog and then see if it is a binary or a script and continue from there.