I think it is better to use the prize with escrow to have more validity
I see no reason to include an escrow in this situation and also pay for their involvement. You won't be working for the OP or offer him your services in a way where you could get scammed. You will be predicting the results of football matches.
@BabyBandit
You should consider introducing several rules when the time comes to start your lottery.
You might be interested in doing a nice thing, but believe me there will be many trying to cheat and take advantage of the situation. The rules should say, for example, that participants must have a minimum of 50 posts to play. No new accounts registered after the creation of this topic. No alt accounts. No post editing once the posts have been made, and stuff like that. After all, you don't want to give cheaters increased odds to win the reward.
Yes, but most lottery only serves to deceive and obtain merits.
You have to be a little more legal, right =)