"Exactly," Adrian said flatly. "There was no wiggle room for him on this. If he somehow failed, it was unlikely he'd get another chance like this again. If he succeeded - no, when he told himself - it was uncertain how well the ministry was reward a job well done. "Not in front of the ministry," Adrian corrected. "Within. On a night when there was public access, meaning anyone could have been in the atrium." That much was public knowledge by now, so he wasn't revealing anything he had to keep close to the chest.
At Theo's question, Adrian took a moment to take another drag. "There's nothing to support that at the moment," he replied. It was a bit evasive, but completely true. There was nothing to support it, and Theo hadn't been clear as to which deaths. Adrian suspecting Harry's and Zurlo's were connected, but had no proof yet. As for the other murders, they could be as well, but again, no solid evidence to prove it.
That's what made the whole thing so bloody frustrating: the lack of anything concrete to go on.