I know that you believe in leveraging 3rd party resources such as YouTube, and when it's appropriate, I do, too. However, this is a revenue stream for this client, so the more I can secure the content *and* display it in the manner they've requested, the better I'm doing my job for them. That's the joy of creating custom solutions, after all, isn't it?
I never suggested that for this scenario, I only recommend that when appropriate myself.
You asked for suggestions about securing video, so I shared what I know about it. Of course how secure does it really need to be is what should decide how to implement it. If it just needs to be inconvenient to get the video file (which seems perfectly reasonable to me) then it will be an easier implementation than if it really really needs to be as secure possible. Inconvenient for a technical user or hacker is about equivalent to impossible for non technical users and that may be good enough security in some scenarios such as this one.
Best,
Joe