Just throwing this out for discussion.
One thing that the amazon women were know for was that they capture men to use as their slaves. Could something like this be worked into the swap? I think it would be interesting to have a number of women go to Tambaqui and have the remaining get to pick which men they want.
(They also cut off their right breast -hence the greek name given to them a-mazon, or, without breast) I think this would get way too expensive for Heidi)
I think the whole amazon women thing has been a little overlooked and we know how they like to work in local folklore.