qq is going to beat j5 86% of the time, that leaves 14% of the time for you to lose. You also need to take stack sizes into account. At the final table if someone has 50 big blinds and you have 4, they probably don't care what their cards are, they aren't risking that much and the reward for knocking you out is worth the risk.
Hi, it's the first hand I played in that freeroll, it's not the final table. I thought I got lucky so I was allin with pocket Q.
One guy told me maybe that guy who called with 5Jo may have many accounts in betcoin, so he can all in with every hand. If he lost, he can log-in with other accounts to play. I think that's very reasonable explanation. And the other explanation: he is a lucky bad player, lol.