Okay, lots of topics to address.
The Gatekeeper Before Molly's phone call, Harry was going to use LC to investigate black magic. Without the Gatekeeper's message, Harry wouldn't have been planning on using LC to track black magic. Instead, he would have been looking into the Eb's request or investigating the accident. That said, I think there is too much evidence the Gatekeeper doesn't want Harry dead and that the Gatekeeper could easily kill Harry and make him disappear to believe that the Gatekeeper is trying to get Harry to kill himself.
The significance of the accident JB is a lazy writer and doesn't introduce events that don't have a significance. Granted the significance might be character development rather than plot development, but there really isn't much character development in the fact that Harry can be the victim of random accidents, so I doubt that is the case. Now, the accident was the means JB used to prompt the Harry/Murphy conversation, and it's purpose could have been limited to setting up that conversation. However, like Uriel, JB likes to kill two birds with one stone, so I think the accident will have later significance. Specifically, I think Harry will discover the attempted murder was a moment-of-opportunity attack by someone who was present in Chicago for the execution and saw an opportunity to possibly remove Harry as a problem.
The interrupting phone call This event is entirely separate from the accident. I reject the theory that the accident was designed to delay Harry so the phone call would be in time to save him. First, as indicated by the cop's comments, the accident was far too serious to be a benign attempt to save Harry. Second, there was far too much time between the accident and the phone call and the phone call was far too close to the start of the ritual for anyone to have planned it so precisely. If anyone could accurately predict the exact time that Harry would use LC, it makes far more sense that they would manipulate the timing of the interrupting phone call than trying to delay the use of LC until after the call. In fact, don't we find out that Molly was prompted/manipulated into calling Harry? Given Lea's backdoor into Harry's apartment, someone like Mab would be able to monitor Harry's use of LC and convince Molly to call at the right time to stop it. Alternatively, someone time traveling might have knowledge of the exact time when Harry would try to use LC and convince Molly to call at the right time to stop it. It's much easier than setting up an accident and hoping it causes a long enough delay to stop Harry from using LC while not injuring Harry too severely.
Lash and LCAdding to the lack of time argument, here is the following:
Lash spent considerable effort to convince Harry not to use LC. If she had known about the specific flaw, her next step would have been to use that as a bargaining chip. Once Harry had proven he was going to use LC at any cost, she would have told him she knew of a specific flaw and warned him that he would never be able to fix it in time to save Molly. She then would have offered to identify the flaw and taught him to fix it, either as part of a bargain (maybe an agreement that he would sit and talk with her for 30 minutes) or as a display of her good will (i.e. making Harry more dependent upon her knowledge). There is no way she has Harry secretly fix it, losing whatever advantage she could have gotten from helping him fix it.
Was LC destroyed Personally, I think yes, but given JB's vague answer, that's really just a guess. However, it's important not to cut off the rest of JB's answer to that question:
It was made of (mostly) pewter. The rest was plastic. Harry hadn’t taken steps to make it less destructible (which would have interfered with its function anyway–it was built to be sensitive, not tough). There was just no way it could have survived the fire. And no, the FBI didn’t confiscate it.
Changes is, in many ways, about loss. About encountering it and feeling its pain. That happens to all of us, sooner or later. There’s no avoiding it.
The real question is, how do you pick up the pieces and keep going, afterward.
I think the bolded part of that quote provides strong evidence that if LC is still around, Harry won't be getting it back. Instead, it will be used to complicate Harry's life, either because it is a powerful tool in the hands of an enemy or because there might be some way to track its creation back to him, which would be bad if the Wouncil found it, or both.
