Local here, and figured it was a good time to chime in...
For those unfamiliar with the site of this project, there's a 60-70 ft elevation difference between the highest and lowest points the coaster will occupy. Assuming the ride is already at least partially fabricated (which seems to be the case based on shipping documents), simply relocating the attraction is absolutely not a likely option as it would probably require significant additional cost to reengineer entire portions of the structure. Much of the terrain work has already been completed at the site, and while that cost was likely paid by old Six Flags before the merger, it is a sunk cost that can't easily be recovered should the project be abandoned. It's also unlikely they could simply stick something else there further down the road without requiring another round of terrain modification.
The permit cited most recently is from last year, and while I don't know exactly what is causing the repeated review failures, it is not the only thing related to the project that has been filed on the LA county site. Since the beginning of this year, there have been at least a half dozen new filings, with the most recent I'm easily finding dated in July of 2025. If the coaster were to be canceled or redirected for financial reasons, it is highly unlikely those would have happened as the decision on the ride would likely have been made earlier in the year. It's been stated in this thread as of late September that press materials were being prepared, so unless that was erroneous we know the project was still on as of a month ago.
Will it still open in 2026? I am personally not yet ready to rule that out. SFMM is a year-round park with a habit of opening their attractions in the back half of the year, so I could very well see that being the plan for this attraction. While we don't know the exact size of the ride, Siren's Curse was eight months from the start of construction to the ride opening and SFMM's last coaster on the hillside (Full Throttle) had a very similar build timeline, so there is precedent for it. If we don't see any work on site by early next year (and haven't heard anything about the ride by then either), that's probably a pretty good indicator it's been postponed.