My best best advices are not listed there - Stop using Google CDNs - Stop using Google fonts - Don't put Google Analytics in the header (or don't use it) otherwise will block/delay the browser load the website. Most of the websites just timeout because of those 3 things and make the website imposible to navigate. If you host your website in a normal VPS, without using Google services you will have a quite nice chance…
I know some enterprise environments are, not surprisingly, not too fond of 3rd-party scripts, and their firewalls could be nearly as bad too.