I found some additional interesting reading about the IWF passing out a list of sites that had some dubious content on them down to ISP's. When the ISP's implemented the blocking of the sites (talk talk in the UK was one of the ones I saw mentioned), it blocked login pages for wordpress on a bunch of sites as well (this was not intended, obviously).
Your reseller should be able to provide support from godaddy. Open a case for this with the reseller and ask for priority support. Ask for copies of the error logs that pertain to your site. If you think it was wordfence (which I don't think it should be, you can always try this:
https://support.wordfence.com/support/articles/1000010321-how-can-i-remove-all-wordfence-data-or-reset-wordfence-to-the-default
The bottom line is that there are lots of reasons for this error, and until you get a little bit clearer indication of the actual cause, it will be hard to figure out how to correct it. I hope we are able to help at least point you in the right direction.
tim
ps I loved the website. Trujillo seems like a wonderful place to visit. I hope one day I will be able to go :)