@Marti Too bad you can't edit here.
Let me try again since this part sounded confusing.

e.g. is the site itself trying to hotlink in this Userscript when enabled ??

When a video requires the extension, a message is displayed in the player (which you probably encountered which is how you ended up on the instruction page).
Some users receive a different error in the player, which directs them to the settings page to enable "force extension", this in turn now shows the first message (that you encountered) and leads them to the installation page. It's the same thing.

If the script was to be removed from this site right now, everyone that has it installed already wouldn't notice anything and it would function exactly the same.
A place was needed to host it where it could be updated without Chrome throwing security errors, so it's here.

The script is tied to the player. So for example, the player makes a crossdomain flash request to the source, which might fail, resulting in an error for some people. That's what force extension option is for, instead of relying on flashes crossdomain it utilizes the GM_xmlhttpRequest. The extension page is just for instructions (when force extension is enabled) or in other scenarios where it is required, so yes they are the same thing. Some people just don't need it that's why the option is there.
It doesn't "hotlink" anything and runs independent after installation from this site, if that's what you were asking

@Marti , @noframes has been added.

@Marti I will look at @noframes and see what impact that has, however there are no iframes used anywhere and the player simply will not load in an iframe.
Also keep in mind this script has been on here long before the fiasco started (unchanged) and had no issues (as far I'm aware), it should not be pulling the source under any circumstances (unless there's some update issue still), and is completely independent

@Marti What do you mean by "raw installs"? The traffic spikes on the weekends. Monday and Tuesday it spikes as well. I'm not sure what @noframes accomplishes as the player already has an iframe breaker and will not work if iframed, thus not using the script ever (it only uses the script on player load) and is completely independent after installation.

Are these requests all from tampermonkey? Because there are many greasemonkey users as well, and if there are no "raw installs" from these users, this should isolate the issue to tampermonkey

You clicked install too many times. This site limits that, try again in a day.
@Marti What do you mean by "constantly hit the site"? It is completely independent after installed. If it constantly hits the site that's an issue with tampermonkey

you didn't install tampermonkey.

get tampermonkey from the chrome app store