What picard is and isn't experiencing while he is locutus is left pretty ambiguous. Picard might have realized something in his regular form that Locutus wouldn't. The small part of Picard left in Locutus might not have picked up on it, therefore locutus would have no idea.
I think this is unlikely.
The Borg were able to get enough of Picard's knowledge that they were able to defeat the Starfleet armada and Wolf 359, and they were also able to use his knowledge of the deflector weapon to create a defense for it. So we can conclude that if Picard knew it when he was assimilated, the Borg knew it as well.
Likewise, at the end of the episode, Picard says he remembers "everything, including some brilliantly unorthodox strategy from a former first officer of mine." So Picard was aware of everything he expereinced while he was assimilated.
Therefore, I think that since Picard had been briefed about a plan to use the saucer as a way of distracting the Borg from the more dangerous stardrive, the Borg would have seen Riker's plan as an execution of the plan Picard was briefed on. It would only be once Data and Worf were detected on the Cube that the Collective would be aware of what was really going on. Luckily, Data and Worf were able to locate Picard quickly, and were able to get back to the shuttle before the Borg could adapt to Riker's actual plan.