Yes, I’m assuming that someone actively looking for signs of deception would eventually determine that “Bellatrix” was a deathdoll, especially if the wizard who created the doll intended them to. That seems pretty likely.
As for being convincing… well, unknown agents breaking Bellatrix out of jail with the vial isn’t a sure sign of Voldemort, either, but it didn’t have to be: Dumbledore inferred, entirely sensibly, that the expected disutility of Voldemort’s return given the probability of it conditioned on someone breaking Bellatrix out of Azkaban was high enough to be worth sounding the alarm.
Perhaps you’re right that Quirrell wasn’t confident that Dumbledore (or Moody) would perform the same calculation without the vial. But it seems unlikely to me.
Yes, I’m assuming that someone actively looking for signs of deception would eventually determine that “Bellatrix” was a deathdoll, especially if the wizard who created the doll intended them to. That seems pretty likely.
As for being convincing… well, unknown agents breaking Bellatrix out of jail with the vial isn’t a sure sign of Voldemort, either, but it didn’t have to be: Dumbledore inferred, entirely sensibly, that the expected disutility of Voldemort’s return given the probability of it conditioned on someone breaking Bellatrix out of Azkaban was high enough to be worth sounding the alarm.
Perhaps you’re right that Quirrell wasn’t confident that Dumbledore (or Moody) would perform the same calculation without the vial. But it seems unlikely to me.