Assumptions:
1) Facebook's news feed algorithm is optimized to find viral stories and maximize engagement with them. During the 2016 election, Donald Trump exploited this behavior repeatedly with his many successful PR stunts.
The way it worked was: Trump would make a rude comment, and then everyone offended by it would share the story in outrage. Perhaps 90% of their FB friends would agree, but the other 10% saw the rude comment as telling truth to power. The messages were crafted to maximize this bifurcation.
2) There were efforts by Russia sponsored groups to fund various social media campaigns, both for and against Trump, and for and against various non-mainstream political causes.
Analysis:
Here's where it relates to your observation: Officials realize that #1 above can have real political consequences in the US, and thus view it as a threat to the status quo (which it is).
Facebook did not intend to let itself be used this way by Trump, it just happens to be the profit maximizing evolution of the news feed algorithm after many years of R&D.
Officials suddenly realize both the threat that the news feed poses, and also the opportunity it offers. To make the point clear, Facebook can in essence be a softer version of a Great Firewall, combined with a built-in social credit system, not just for the US but for the world.
Facebook made clear its stance on working more closely with US officials when it announced that under $150K had been spent by Russian-funded interest groups in the 2016 election, but that was not enough to satisfy officials.
As the pressure on Facebook slowly ratcheted up, Facebook announced human reviewers for controversial content, new content guidelines, the eviction of various alt political personalities, etc. This too was not enough to satisfy US officials, who remained concerned about weaponization of the platform and who didn't like Facebook's attitude.
So pressure continued to increase, as evidenced by the PR released by FB which attempted to put Sandberg in the spotlight for missteps. This is a common tactic, akin to Rumsfeld being in the spotlight about torture to shield GWB from scrutiny.
We can see now that scapegoating Sandberg didn't work, though it did buy a bit of time for Facebook to formulate its strategy and hunker down.
So now US officials are spreading the news about various privacy breaches in an attempt to spook investors and force Zuck to come to the table and allow the Great Firewall + Social Credit system that officials want, which will guarantee that no upstart candidate could ever leverage the news feed algorithm to get billions in free marketing budget ever again.
As others point out in this thread, Zuck controls a lot of Facebook and is unlikely to be fired.
I personally expect that Zuck fully intends to play ball but is dealing with employees who (like those at Google who scuttled the big China search deal) are not so ethically adept as to convince themselves that handing the keys to US officials is appropriate. My guess is that FB has such solid internal analytics that it would be impossible to hide such cooperation from the many employees who are laser focused on various metrics and KPIs of the algorithm and its associated revenue streams.
So what is happening is a sort of dance during which both players are watching to see how public opinion evolves before they make their next move. US officials probably have a few fairly impressive cards they have not played yet, and would probably strongly prefer not to play them. I'd also guess that there are efforts underway inside Facebook to create the mechanisms US officials want in a way that may take a bit more time but will not spook the workers.
There may also be a plan to have some innocuous-seeming laws passed such that compliance will give FB the excuse to gut/rebuild various aspects of its algorithm's analytics which allow it to embed the firewall + social credit monitoring hooks without alarming those working on them.
At this point I think the dominant factors are the reality that Zuck does plan to fully cooperate and that there is an unexpected level of urgency from US official to make this happen sooner rather than later. I suppose if you add up the userbase of FB, Instagram and Whatsapp it's clear why the officials are chomping at the bit to get the analytic and censorship dashboards up and running ASAP.