AR Refund in AP when sub-recipient send some payment back

Hi,

I'm trying to figure out how to deal with scenarios where after sub-recipient invoice is paid they send some money back claiming that prior invoice overcharged so they are sending money back. I came across a prior inquiry for the same topic and found that Oracle specialist provided Doc ID 1085957.1 which details the steps. This is the case where refund is processed in AP via AR.

Can you please explain what do the $1,000 ( a prepaid voucher created) and $800 (a regular voucher) represent? Is this prepaid voucher truly generating a payment that will be picked up by Paycycle and go to vendor (supplier)? This is a pint where we are getting a little confused. Any explanation would be much appreciated. We understand how the processes in the document are executed in the system but again, we need to understand the premises.