Alright something just occurred to me and this is just a thought but everyone knows the terminals that fzdw11 mentioned earlier about the unidentified craft Spark finds on Halo yes? It contained the same gases that his Installation does. Spark says it was leaking atmosphere in many places and no organisms escaped the craft and that it was emitting a short ranged distress signal over and over but he had to block all communications.
http://artifact.at.ua/index/0-26 This artifact contains trajectory coordinates and goes along to say the replacement coding for Installation 010 was ready and a beacon was sent out and at the bottom repeats the words "repent repent repent." Anyone see where I'm going with this? I'm not sure why Guilty Spark couldn't identify the ship class but what if the beacon sent by 69086 was that ship and "repent repent repent" was the distress signal sent in a different language? Could this mean AC could be the monitor of the new Installation 10.
The problems with this theory however is that it doesn't explain why Guilty Spark couldn't translate the language or identify the type of craft that came down it only explains why the atmosphere inside was the same and the coincidence of the distress signal. It could've been short range because he wanted it only to reach inside the radius of the Installation?