There's a group of people who talk about bypassing Apache and Nginx filtering, but in fact, there's no such term at all. In past years, Apache and Nginx hosts worked, and that's true. But the reason they worked wasn't the host, but the DPI.
DPI at the time was weak; it didn't care whether you sent a payload directly or via a proxy. DPI only looked at the contents of the payload to see if there was a host affiliated with the company. When it found one, it would give you the connection. You'd then get the response from the proxy, not the actual host. Now, however, DPI has been updated and now checks whether you're trying to send the payload directly or via a proxy.
In short, if you find a host that gives a specific response but is unable to give you the proxy response, it won't work, even if the actual host gives you 200 OK.