An arbiter could communicate between the parties for verification. All the addresses are in the transaction.
I had not explored Bisq enough to know where the seed and date were.
Everyone, please backup your Seed & Date before using Bisq.io
The main screen has Funds & Market.
When I first used Bisq.io I was a Novice. I wish I had started as an expert.
I now understand to save the seed and date.