In the case of two sets of electors, the one with the Governor’s seal is most likely to count.
Can’t say that wouldn’t happen. But I can see the Electoral Count Act of 1887 etc. and the SCOTUS, for what it’s worth, being involved in that case. If it comes to a governor and legislature etc. submitting two slates, things could be very tricky. Sadly, it’s going to take more than GA, at this point. But my take from the article is basically the treachery of Kemp.