Mitchum
Deity
If I understand map trades, every tile we reveal is one we don't have to pay for. So we should be able to get any mystery islands + gold for giving him our knowledge which includes Peter's.
But it can't hurt to minimize the # of tiles SB knows that we don't.
The only downside would be if a wb scooted around the south shore while the chariot is scouting the north shore. It would really delay how long it takes to meet them. But I'm fine scouting more with the chariot.