Reading through this thread, I suspect that we’re making too many assumptions about these ancient “rebels”…
The only piece of dialogue I can remember that mentions Azel’s kidnappers is the following line from Craymen:
Long ago there was dissension among the ancient ones. After centuries of fighting…
Now, we know that the Ancient Age involved endless wars between technologically comparable nations. By the way Craymen talks about these “rebels”, they just sound like one of these Ancient Age factions to me. I don’t think they would have been any less advanced than the other side; if they weren’t at a similar level, they would have been simply crushed, rather than there being “centuries of fighting”.
Beyond that, there doesn’t seem to be much evidence on which to base any further conclusions about them. From that description, which is pretty much all we have, they just sound like another group of Ancients as far as I can tell.
The Towers were only built by the other Ancient Age nation, of course. So how could the rival Ancients build Drones to operate something that they would not have access to? Ancient Age technology seems to be far beyond rocket science, and if they didn’t have the blueprints for the Tower I don’t see how they could make a Drone that could operate it. The technology just seems so ridiculously complex. It’d be like trying to make software for a piece of hardware that you didn’t know the first thing about.
Now Azel was made in Uru, and Uru was directly linked to the Tower. In all logic, Azel was probably created to work in the Tower, to interface with it and operate its systems. As far as I can tell, this would be why the rival Ancients needed her. As it’s never implied that this group reprogrammed Azel, I don’t believe that they did. They probably just planned to use her original function - controlling the Tower - for their own purposes.
Now please don’t take this the wrong way, anyone, but saying that this rival group were interested in freeing Drones from slavery seems to be jumping to conclusions a little. As we know that there were technologically cometitive sides in the Ancient Age, it seems more likely to me that these “rebels” we keep talking about were just the other group of Ancients, waging war with bio-weapons and maybe even Drones of their own.