So, in the world I work, I build systems for (as an example) marketing teams to submit these types of messages, have them approved by an approval mechanism, and then deployed in some fashion.
I suggest then, that there is a fifth culprit. The system that is in place (assuming of course that there is one), upon which the marketing team input their suggested text, should check that any URLs in the body of the text resolve properly.
Yes, testing from the Marketing team would have been good, but we all know that even development teams have problems in this area when it’s manual. I think we could break the actors down in a different way:
1.) Content creator (Marketing team)
2.) Content management system/service solution
3.) Release management
5.) Consuming applications
6.) Webservers receiving the URL from the consumer app
I think that the problem is at points 1, 2 and 3 of this process. 4, 5 and 6 have functioned perfectly, and putting sticking tape in place would only introduce technical debt in those areas.
You can blame the marketing team, but that gets you nowhere, there is no solution to be found other than saying “please don’t do this”.
You can blame the release process (testing etc.) absolutely, and more testing would have been good, but in pure release terms, the content that was asked to be deployed was deployed properly.
So here (and I rarely say this personally) technology could have prevented this. It is technology (VM’s webservers) that has stipulated that the URL must be of a certain form, so Virgin Media’s own technology (the CMS) should have ensured that the content put out by the marketing team matched up to their own standards expected by their webservers.