I managed to get it to enroll admin. I did two things and I'm not completely sure which of the commands were where the magic happend.
I did the following:
$ npm install grpc
$ npm install --python=python2.7
The second command was due to the fact that the prerequisites was python 2.7 - even though it was written for Ubuntu user only in https://hyperledger-fabric.readthedocs.io/en/latest/prereqs.html
I hope my post can help others in the future, like you two helped me!