I escalated to our account manager who said somebody would call me yesterday morning, but then instead I got an email saying that they won't support us customizing the URL (or having a fake URL as they put it), despite the docs saying:
You can customize the URL and querystring which are sent with the data object in the second argument.
They also gave a bogus reason that they filter out stuff for abuse and spam prevention and said stuff has to be on our domain (which it is). This also isn't true since all our random dev domains record actions anyways.
Since they seem to be so caught up that me logging page views at /_event/... isn't cool, I just made the URL an actual page, and submitted another screencast to them showing that this still doesn't work, even if it's a real page. Waiting to hear back from support escalations now.
Separately, another support rep just told me that the case sounded like something they'd be able to handle, but that I just need to keep hammering escalations until I'm heard.