When I go on a team hunt my expectation is that I will receive only the items that arrive in my loot window.
When I get a PM from a soc mate saying "I owe you X peds" from whenever, I am happy!
When I get a PM from a soc mate saying "You owe X peds from the hunt cos you looted <item>" I check my storage, and 'Low and behold' there the item is. I then pay up. what goes around comes around.
If I was teaming with someone I did not know, I would make it clear that "What you loot it what you get!"
Then I don't lose anything when they loot a nice item, as I never expected to get a share. Should they then split it, A friendship is formed.
I do OC split fairly regardless of "What you loot it what you get!", but by making it clear they keep what they loot, it's their choice to be fair or not, and I know I will be fair.
Doubt the case in question will be resolved to the satisfaction of both parties though.