I am quite sure the proper way to resolve this problem would be to change the said policies.
I think the thing is that you cant change policies on your users companies
But users can also have arbitrarily horrible policies that will restrict any possible thing you might like to do. No images loaded, for example.
Same for me, both this domain and nyud.net are blocked because they're classified as proxies.
For some reason the DNS servers my Swedish ISP provides seems to ignore/block all lookups for anything containing nyud.net. I have never encountered anything at all being blocked before with my ISP, so it seems a bit strange. Too bad if other ISPs also are blocking CoralCDN. I tried Googles DNS server (8.8.8.8) and everything works fine with that.
It is also blocked by the "Low" setting of the OpenDNS content filter, a fairly popular service and setting.
Well, you can use it to trivially get around all other blocks. Points more to the futility of trying to block "bad" sites name by name than anything else.