We may be dependent on AG & TC for that, but I certainly hope that LE asked them who called and double-checked that with call records, interview with the person who called, etc. The removal from the timeline probably does reflect a problem with that account, but we don't know for sure.
In terms of news outlets, the Daily Mail said she hadn't attended church in person since the pandemic. Brian Entin also heard that she wasn't attending St. Andrews Presbyterian but figured she was going to another church. With regard to attending St. Andrews virtually, I've heard that one can't tell who's on the livestream, but I've also heard that there are parts that are like a Zoom meeting so you can tell...
The New York Times stuck with the original account, namely that a churchgoer saw that she wasn't "in the pews" at church. I think ABC said something similar.
All of this is to say that it's not totally clear whether a fellow churchgoer could've reported her missing either in person or virtually. Those who believe that the SIL was involved in her disappearance may tend to favor the reports that she wasn't there. I don't know.
JMO.