They didn't certify them either.
Constitutionally the legislature determines how electors are chosen. In the past election that was done by the voters. If there is to be a competing slate of electors then the legislature has to chose them. Yesterday none of them did.
The text of the relevant part of Article II section 1 is:
Each State shall appoint, in such Manner as the Legislature thereof may direct, a Number of Electors, equal to the whole Number of Senators and Representatives to which the State may be entitled in the Congress...
Thus it is the legislatures job to direct the process, not to necessarily implement the process or certify electors unless they had already decided that they were the ones to implement the process and certify electors. It is not necessarily their job to enforce it (although it would be nice if they would). I suppose in theory the legislature could have declared that the process was not followed and declared a new process after the fact in which they simply picked the electors themselves. But just because they did not do this does not make it magically the case that the manner they directed was not violated. They do not have to take some action to make the electors that were certified illegitimate.
It would have been nice if the Supreme Court weighed in, but they chickened out. And the state courts are part of the problem.
So come Jan 6th the certified electors will be illegitimate in these states, even though they were certified. And on those grounds the election could be contested per the 12th Amendment.