Is nitter.net still functional for you? The service was accessible earlier this year from my location but now it is all 403 Forbidden.
iirc, twitter turned off all anonymous access, unless you come from a search engine, then you get a limit number of requests. So zedeus came up with an idea to make a massive pool of search engine'd api tokens and use those to keep nitter up. The mirrors would have to copy that idea, and few (0?) have atm.
I think the token workaround you mentioned is the old way that no longer works, but I am not sure.