I just finished rereading MB1 over Thanksgiving, and was curious about one of the plot elements.
Near the end of the book, after Kell destroys the pits, the Renoux crew are in the cages coming down to be executed. At first, everyone thinks that this is because of Marsh being caught, spilling the info about them. That makes sense. However, reading that part knowing that that Marsh wasn't caught makes me wonder, how exactly did they all get caught?
I"m by no means a careful reader, so I could of missed something obvious, but the last I remember, Kell gave them the order to leave town, they did, and the next time you see them, they are in the cages. How were the found out? The only ideas I could come up with (neither which I think have any direct evidence in the story itself) is either that an inquisitor somehow saw them leave, and since they evidently (as is implied earlier in the book) have some method of detecting Renoux (why he couldn't attend the balls) they saw he was a Kandra, and then took everyone hostage. The only other thought that came to my mind was that they somehow traced Vin to that residence (just like they discovered the thieving crews) and it was just a coincidence of when they actually were found out.
Also, a smaller plot point that I just want to clarify. When Kell destroyed the pits he destroyed some of the crystal nodes as well right? Straff mentions something that happened "a few years ago" that caused their production to drop so they couldn't quite keep up with what the Lord Ruler wanted. I think reading the scenes with Kell in the pits, there is some text that makes it appear that he got a few of them when he escaped.