User blog comment:Brianbreed/The Biggest Single Plot Hole in Mass Effect 2/@comment-152.78.234.231-20120313002148

The Omega-4 Relay is STATED to be two-way: on multiple occasions, people say that only the Collectors can go "in or out" of that thing. Presumably thanks to their IFF that causes it to send them to a more precise destination. Jumping in, you need the IFF because otherwise you will drift into a black hole and die. Jumping out? No such problem, since there are no black holes near the Omega-4 relay. And if you say that they jumped out via FTL, then there is, again, absolutely no problem: they only needed to get outside the radius of the blast, and as FTL jumps are perfectly controllable compared to transit through a Mass Relay, the Normandy would have had no problem getting out of range in time, and then being able to travel back to go through the relay.

And as for the Seeker... Didn't they pick it up on Freedom's Progress? If not, then I'm sure some other Cerberus team would have been sent on a do-or-die mission to retrieve a seeker bug from a lost human colony. Hell, maybe they even found them earlier but had no idea that they were with the Colectors!