With the merge of Cybersun ship this issue will keep showing up in rounds more often than usually. Normally I've faced this problem with free golem AIs, who are thankfully usually Asimov with a law 4 to treat golems as humans, or when I'm malf and the borg factory starts spewing out borgs synced to another, asimov AI. Oh boy those are fun. In the case of borg factory I imagine a code solution would be in place, but it is hard to assume a roboticist on the station would be aware of AIs being built on the drone station, free golem ship, derelict station or Cybersun ship. Cybersun in particular becomes troublesome because it is extremely unlikely to be asimov. There is no intent from the roboticist to build a cyborg that immediately murders them and starts sabotaging station. Borg on the other hand is compelled to follow their laws even if there's no IC explanation to as to why it has been linked to something the crew is not aware of. Vice versa, it would be very awkward if Cybersun agents built a borg that was slaved to the station AI.
I had a quick glance through rules and headmin rulings, I did not find anything related to a borg being slaved to a wrong AI. In my humble opinion this comes down to rule 1: don't be a dick. A borg who is clearly synced to an AI who has no connection to the people who actually built the cyborg should have good faith in their builder and inform that they made a mistake. Doubly so for borgs created by borging machine.
Spoiler: