No, it is very typical in cases like this for the Church to wait for an actual guilty verdict before moving forward with any disciplinary actions, including excommunication. Also, it's essentially impossible for him to have been excommunicated before he returned to Idaho in February, based on the process involved (meetings, where he could not have been present since he was in HI). I think it very unlikely they would have moved on him before Covid lockdown because there were too many who were uncertain about the status of the kids (having known him and not being able to believe him capable of murder). Now that he's in jail I think it's very likely they will wait for the legal process to determine his guilt before excommunication, unless he confessed to a church leader that he was guilty or somehow made the effort himself to remove his records from the church.
ETA: occasionally people are excommunicated without being present for the meetings, but that is rare. I also think his local leaders would find it hard to believe the allegations against him and would not have moved on him over "allegations"--very much like innocent until proven guilty. I'd assume he's gotten lucky and not had to face most Church issues (even just regular interactions with people) since Covid shut things down.
ETA 2: this is not from the official manual, but from Wikipedia and I believe it is accurate:
"The LDS Church has instructed leaders that a disciplinary council is mandatory when evidence suggests that a member of the church may have committed any of the following offences against the standards of the church:
[1] Murder;
rape;
sexual assault conviction;
child or youth abuse;
abuse of a spouse or another adult; predatory behavior (violent,
sexual, or financial);
incest;
child *advertiser censored*;
plural marriage; serious sin while holding a prominent church position; and most felony convictions."
So, this means that now that remains have been found, they may hold a council (meeting), but there may not be enough agreement to excommunicate until he's actually convicted. It happens at the local level, so it just depends who is on the council and how they feel about it.
MOO moo moo