Investigation Arc Into Jasons Death in Gotham Knights #42-#45.
As requested by sistermagpie, this is the arc where Jason's death is being investigated in Gotham Knights.
Gotham Knights #42 [1 scan] A social worker looks into the suspicious circumstances around Jason's death, but with Alfred sick, Bruce is in no mood to cooperate.
Gotham Knights #43 [2 scans] Bruce later reminices about Babs' adventure with Jason and wanting her opinion. Babs then comes down to the depths of the cave to talk to him about it.
Gotham Knights #44 [5 scans] We're given background on Jason's case and see how Bruce is reacting to being investigated.
Gotham Knights #45 [7 scans] The guy shows up and does his interviews.