Batman trusted Dick and Miaomiao's judgment.
If neither of them nor Pamela and the Three Sisters could find anything, the likeliest explanation was that nothing had been wrong with the gifts to begin with.
If the problem wasn't with the gifts themselves, it could only lie in the act of "giving gifts."
Gotham's gangsters and major villains were all old hands. Even if they had noticed that the Gotham Phantom's Three Sisters were different from before, the involvement of the Bat-family of vigilantes made things more complicated. That only made them less likely to go after Harley Quinn so soon.
Even if they were going to act, they wouldn't do it now-during Gotham's rare peaceful Christmas.
The abnormal deep slumber of everyone in Arkham, the villains' collective silence, the inaction of Gotham's factions, large and small.
Making a move now would be no different from exposing themselves to everyone's scrutiny.
Unless-
What had happened to Harley Quinn stemmed from a danger planted much earlier.
The Joker, for instance.
"Isn't the Joker still in Arkham?" Dick couldn't help interjecting. "Little Fish's singing still has them all sleeping like good little babies."
"He doesn't need to act himself. No one needs to do anything at all." Batman's voice was low, as though weighed down by a layer of Gotham's heavy rain clouds. "The psychological imprint he left in Harley's brain is harder to dismantle than any bomb."
Batman tapped his multifunction watch, and Harley Quinn's past treatment records, behavioral patterns, and several repeatedly flagged surveillance clips of her with the Joker appeared on its miniature screen.
"Harley Quinn may seem to have broken away from the Joker, but her actions and thoughts still follow his logic. She can't escape it."
After all, Harley Quinn's very alias marked her as the Joker's girl.