Hi guys.
I had a similar issue to yours, and tried removing local by flywheel and virtualbox manually, and reinstalling several times. It didnt work until i also removed the docker folder in my user directory along with virtualbox and flywheel, and finally ran a cleanup tool called Puran Utilities. I dont think i altered the registry files, but I think it got rid of the final pieces. Flywheel is working now anyway 
I recommend that you try removing all files and folders left behind by flywheel, virtualbox and docker, and then try installing the latest version. I almost tried virtualizing a windows 7 pc with Hyper-V, but didnt get around to it. That might be another solution thats worth a shot if you are stuck with a broken installation. Virtualizing and environment for a virtualization engine is kind of funny when you think about it, so I might just try it for kicks 
I hope this helps others in this unfortunate situation, and I would recommend that local by flywheel gets an uninstall option to remove everything upon uninstallation.