I’ve found my answer using Reddit:

If it gets connected to iTunes or Finder and when trying to restore it it throws the error 4013, then either the NAND has failed or it is a problem with the CPU. And since it is commonly known that the CPU soldering of this the iPad 2018 is bad, it is most likely that.

I won’t buy it. None of the 2018 models. It‘s better to be safe than sorry.

Edit: (I feel like that guy from that one Internet forum you once used who had the same problem years ago and actually went back and wrote how he saved that brown)

Edit 2: back in the days, everyone was a man on the internet. Men were men, Women were men. And little girls were FBI-Agents.