After beating the two minions he sets on you and opening the door go into that room and he should be standing there to talk to. If he is not there I would submit a bug report and just leave and reenter to see if fixes it.
Unless you died during the fight against those minions. Then he escapes. If so the only think you can do is beam out wait for it to reset and start over. It,s the only mission you can fail. Might be because of a bug but I liked it that way.
Comments
/rimshot
No need to...we're not the ones that will be interrogating him.
That's for Starfleet Intelligence to do.