Bo left his family, and 6 mos later enjoyed Christmas with them, plus Shawn D. Belle & Claire. AT that point in time he was still on his own. Whatever happened or he decided to do after that is something we don't know, I guess. He still was contacting his family for a while, but then nothing. So.....I don't care what undercover operation, or if he was taken prisoner, or whatever back then.
The fact remains, he left his family to go joyriding around the world. He should have returned home with them after that Christmas, but instead, stayed on.
So, yes, he obviously has been held prisoner, tortured which is horrible, and I sure hope those scenes are over. So, add me to the "not invested in Bo's return" group.