Well, this is wrong to say. How could I know whether thread was copied or not by bot as far as thread leads to productive discussion.
You shouldn't be caring about your signature campaign earnings enough for it to be an issue.
Is there a way one can even know the exact one that has been deleted because its only the last post count that change.
Not that I know of, unless you manually recall all threads you post in. Not that it matters though, since the thread would be gone.