True, i guess trust would need to be earned some how, maybe contact the puzzle creator about the reward and submit the addresses of the members of the "team"
You can't earn trust any way from the I see it. First of all, how is anyone going to know who solves it? What would the puzzle creator do with the addresses?
The only way that would be possible would be to have a KYC for the puzzle, where everyone register in person and there is only one valid withdraw address per person and they can then enter in groups. It would be like Ready Player 1