I found this document which lists all of the timeline for Michigan certification: https://campaignlegal.org/sites/default/files/2024-09/Michigan%20Guide%20-%20Final.pdf (apparently this has been on a lot of folks' radar for awhile :)
that document makes it clear that in Michigan at least certification is a mandatory duty in both the constitution and by state law.
You are 100% correct to worry about this, of course. That said, I don't see something more than 3.6M people (half the registered voters of Michigan to just pick that one state as an example) seeing themselves disenfranchised like in your scenario being silent about it and calmly waiting for the courts. I guess I'm saying the perpetrators of such a scheme would have more to worry about than just losing a court case.
On a side note, its interesting that in Michigan it appears that as of today 41% of registered voters have already voted.
https://www.michigan.gov/sos/elections/election-results-and-data/voter-participation-dashboard