Well, did a
rm -rf ~/vagrant.d
sudo rm -rf /opt/vagrant
rm -f /usr/local/bin/vagrant
sudo pkgutil --forget com.vagrant.vagrant
and had a vagrant up that just installed the plugins:
vagrant up
Installing plugin vagrant-bindfs
Fetching: vagrant-share-1.1.9.gem (100%)
Fetching: vagrant-bindfs-1.0.11.gem (100%)
Installing plugin vagrant-hostmanager
Fetching: vagrant-hostmanager-1.8.7.gem (100%)
`vagrant up` must be re-run now that plugins are installed.
Afterwards I could run the box again. Took me like two hours to work this out… Finally done now.