I can complete the quest by giving the recordings to Roscoe (but that wouldn't be my preferred ending). I have raised the issue with Obsidian and had a dialogue with with a support engineer at Private Division. They asked for a save file which I provided and they confirmed that they can reproduce the defect and that a simple edit to the save file cannot resolve it. The Private Division support engineer said that he had passed my save file and the description of the bug to the QA team. I'm probably being naïve thinking they will actually fix it but fingers crossed.
I've not heard of anyone else not being able to complete the quest using the Roscoe route.
