Again on more time for the general question of whether a sub can be "forced" to surface without being attacked, it cannot. BUT if the captain has any intention to keep the acoustic (and whatever other means of detecting subs) signatures hidden from, they would surface.
In this case, it's impossible to know whether the USN sub surfaced before, during, or after efforts to detect or actual detection.
They could have surfaced to pre-empt Chinese attempts to try and detect... they could have surfaced after being made known by the Chinese that they've been detected (which is an interesting statement and choice to make for plenty of reasons) ... they could have surfaced close to the CV01 to let the PLAN know it sneaked in close to the PLAN CV undetected. We don't know. It could be humiliating to the US, to the Chinese or to neither. They could be playing around, they could be doing some double bluffs and feeding incorrect information on purpose etc. Again it's impossible to know the true intentions. It's already impossible (for us) to know the actual event and its finer details.
But for a general situation of arbitrary submarine and surface anti-sub efforts, the submarine should NOT be continuing its usual stealthy operation under the surface while it knows that the adversary anti-sub efforts are trying to detect and track it. Why? It's simply because allowing them the time to calmly go about these anti-sub mission is giving them many golden opportunities to test things out and verify whether or not they work etc.
Now you can see where the mind games could come in and be in effect on both sides.
