Probably not practical to redo the vote in time. So if the State can't certify the vote, I think the power to pick electors then goes to the WI state legislature, which being GOP is likely to choose Trump electors (unless they fear for their lives due to threats from Marxists).
Somebody on the news said that wasn’t the law in Wisconsin. It’s by popular vote. Don’t know if it is true because they lie so much.