On June 21, Larry Elder won a court order in Sacramento Superior Court, putting him on the September 14, 2021 recall ballot. See this story. The case is Elder v Weber, 34-2021-80003682 in Sacramento Superior Court.
The basis for the decision is that the law requiring gubernatorial candidates to submit their income tax returns only applies to primary elections, and the gubernatorial recall is not a primary. This means that none of the other 41 candidates need to have bothered to have submitted their returns. But of course no one could have known that for sure, at the time of the filing deadline.
So far, there is no written decision.