It says in the article that the police were alerted to bracelet tampering: "The filing said the authorities got suspicious that something was awry with the GPS device on March 6. An agent spoke with Ceglia on the phone and "Ceglia reported that the bracelet had been damaged in a fall." But the agent said it subsequently was "functioning properly" until the next day."
This implies that these things must throw false alarms with some regularity, otherwise this would have been a huge red flag and they wouldn't have hesitated to follow up immediately.
This seems likely. Even if you get him on the phone, you could have an officer drive by sometime in the next day to visually inspect that the ankle bracelet is still there.
(Of course I would get a second bracelet and strap a dummy one to my leg to show to the officer. Officer would need some way of verifying he's seeing the right one.)
I might be wrong, but I think they can remove the bracelet temporarily to charge it.