This link is working for me:
https://web.archive.org/web/20170628061344/https://www.youtube.com/watch?v=eTmNWY0ZPfM
You?
You can find other copies on YouTube here: https://www.youtube.com/results?search_query=The+Architects+of+Western+Decline%3A+A+Study+on+the+Frankfurt+