What Fulano said.
If they were attending meetings, "highlighting" their WT with multi-colored markers (so the bro's walking the microphones could see), singing, and following along in the Bible, then you assumed repentance.
Either that or the Holy Spirit would sent a message to you in your sleep to reveal their repentance.
Still, more recently there is talk of it needed to be a year before reinstatement (+/-). They are wanting to try to be sure that a person isn't just faking it to sneak back in and the just disappear.