Perhaps people should request an escrow before posting their finds, as they will just be wasting their time if its the right match and he doesn't end up paying.
yuppp everyone here want escrowed funds first to prevent didnt paid. but this time i want to try his trust

Why would you want to try things and things like trust specially incase of a newbie ?
With an escrow, you are safeguarded. I will prefer using an escrow, even with someone who has a positive green trust, as there is no harm in that.
i know , so can you force him to escrow his funds?

If you mean that I should ask him to do that, then I would say people who have found the t-shirt should do it. Else, just expect to be paid nothing by working on their searches.
Perhaps people should request an escrow before posting their finds, as they will just be wasting their time if its the right match and he doesn't end up paying.
People will never lear from their mistakes, it is normal

. However I do not think the OP will ruin his reputation for 0.20 bitcoin (but who knows, everything is possible!).
I have seen people ruin their reputation for a lot less. And right now he is a newbie, and his account probably has 0 value. So no reason for him not to just create a new account and not pay for the bounty.