PokerTracker

Currently using PT4 for Zoom.

Will PT4 record a hand's action even after hero has fast folded?

For example, we're in the CO with a trash hand, we click fast fold and move onto the next hand. The BTN opens, BB calls and all the money somehow all go in on the flop with the BTN win at showdown with top set (AAT8). Will PT4 have recorded this hand? Also will PT4 have accurately added this data to the BTN and BB's database for HUD use in the future?

Thanks

Yes. PokerStars writes hand histories for all hands you play, and PT4 will import them all.
Just be sure to leave your table window open for a couple of minutes after you sit out so that all of your recent hands can finish playing out. If you close the window immediately any unfinished hands will not be written, and therefore not imported.