Question #1, I just found the command: flow kill individual in debug.
Still looking for direction for the second question.
This question came from a recent problem where no sessions could be established for one VIP, while all others were processing normally. The affected Web servers had been updated and booted individually, and the intervening Reverse Proxy server was also being updated. However, sessions were failing at a point when all components should have been fully reset and "clean". It is not clear what triggered it, but the VIP finally started responding. I can't correlate the resumption of the VIP working to a specific reset or timeout value.