In my own opinion, it is not up to you to tag him with a negative trust, what I think you should do is what you have done, and that is reporting him the bounty manager, is it up to the bounty manager to tag him with a negative trust, and if necessary, ban him from participating in future bounties..
So what I will advice is that, you wait for response from the bounty manager, he is the one to handle the case in the best way, you can tag the user later, but wait for bounty manager to tag him first plus take other necessary action on him.
So you want me to remove my tag and let the bounty manager handle the situation first?
It's just your opinion right? Coz' I have already tagged the user as it is not acceptable for me whether bounty or no bounty that he is taking advantage of my content that is not his and claiming it as his own entry without permission or consent.
The bounty manager doesn't have reputation either if he is willing to cooperate with me on this issue or not.
I will also try reaching out the Jot Art team themselves who have connections with the bounty manager to attend to this important matter.
Since you have tagged him, there is no need removing it, but I want you to know that the final decision still falls bounty manager, he is the one in charge of the campaign, and as such it is his responsibility to look into issues like this, he is the one that will check and confirm of a truth, that the user in question entered the video bounty with your content, he is the one to nullify that user's entry and deny him payment, he is the one to decide whether to ban him from participating in future bounties, it is also his responsibility to report him to DT members so that they can tag him, with the tag from DT members, no other bounty manager will accept the user in to his or her campaign in the future,..
So in conclusion, what I am saying in essence is that, your tag has little to no effect on the user, until bounty manager and DT members step in.