That's quite literally not a way out for these traitors. That will just give the individual states easily winnable cases against anyone that accepts a pardon.
If the non-fascists take back Congress, we can change the current laws & simply extradite the rest of them to the Hague. And we've now seen how fast the federal government can move when it wants to.
At the very least, these traitors are going to be fighting civil lawsuits until they die.
Those laws can be rescinded by Congress, just like any others.