Yes, all social media have open channels with law enforcement. That's because social media have legal obligations and when someone comes to a moderator claiming to be a law enforcement officer working on a kidnapping or preventing a terrorist attack and needing time-sensitive help to save lives, you don't want the moderator to have to guess whether that's a real emergency or a hoax.
It's... not a secret. If you live in a democracy, you can quickly find out the name of these channels, they have websites.
Source: I've been part of a moderation team. Not on something that large, though.
There was no such thing in the Twitter files.
"LERS is a system in which a verified law enforcement agent can securely submit a legal request for user data, view the status of the submitted request, and download the response submitted by Google.
If you are a sworn law enforcement agent or other government official who is authorized to issue legal process in connection with an official investigation, you may submit your request through this system."
--is not the height of transparency, though.
At this point, I think enough of us have lived through being vaccinated that this canard fails to hold water.
(Nothing is 100% safe, and the deaths due to vaccine reaction were tragic. The vaccine was orders of magnitude safer than COVID ripping through the population unchecked).