PayPal payouts are being processed normally on our end. The error message is clearly in regards to your account. You will have to try to escalate the ticket on PayPal to someone who is familiar with Mass Payouts so that they can help you.
I also want to include, that when i got into my itch.io account → settings → Payment processors, i see this message:
PayPal (Legacy)
This is mode is deprecated for the new PayPal Commerce Platform for Marketplaces. Please reconnect to PayPal using the section above to avoid any interruptions to your payments. It is not necessary to remove your legacy account to reconnect to PayPal.
Does this have anything to do with my issue ?