[Varyon]

I think most places, when someone updates a file or similar (like the clerk marking the hearse as "in the shop"), there ends up being a timestamp. If the rental place continues its business on Sunday (it may well close on account of the clerk's apparent suicide), the grieving family who gets a Lincoln Continental rather than the Cadillac they requested is likely to inquire after the discrepancy, and the fact the Lincoln's reservation and the hearse's unavailability were both set around the time the clerk died is going to raise some red flags. If all the data is stored on that computer, it might not be terribly difficult for the clerk to alter the timestamps (perhaps by simply changing the clock on his computer), although he may not even think of the possibility in his addled state. It's more likely that the data is stored on a server that the clerk's station logs into, and he is unlikely to have the sort of access needed to alter the timestamps within the server.

If indeed the timestamps match up with around the time of his death, the worker who discovers this will be rather inclined to inform the police. The service garage the rental place uses may be closed for Sunday, but the police (and his loyal customers) may be able to convince the owner to go in and check on the status of the hearse, particularly considering it may be linked to someone's death (and the mechanic may have known the clerk personally, as someone skilled with servicing classic cars may have received a good deal of business from that location in the past). Once it's found to not be present, and indeed to have not been checked in recently, the police are likely to put out an APB on the vehicle, as it is clearly connected to the man's suicide. By that point, the groups will have already reached Indianola and probably cut it off from the world, but a classic black hearse going down the highway was probably memorable enough of an event (particularly considering a nun was driving it, or was at least a passenger if her friend was driving) that whoever was working highway patrol at the time may well remember and will let dispatch know he saw it heading south. Provided Kessler's sphere of influence catches wind of it, a mysterious suicide linked to a missing, classic black hearse is going to absolutely reek of malign supernatural influence. While the police will be at a loss to figure out where the hearse is headed, and certainly won't get any reports of it once it reaches Indianola, Kessler's group may, through a combination of internet research and dowsing/detection rituals (the latter will be particularly useful if the effect cutting Indianola off from the rest of the world leaves some sort of supernatural imprint), be able to figure out Indianola was the intended destination. They may not realize the Keepers of the Last Hearth are involved, or indeed that there is any connection to the events in Galveston, but will likely try to call some of the businesses there (the Indianola Fishing Marina and Powderhorn Lake RV Park pop up) and will probably know Something is going on when the numbers are out of service (or whatever error the cut-off ritual causes). Certainly, this seems like it could warrant investigation.