Yes we have a reason. Trump threatens media companies and individuals he believes have wronged him - loudly and often. If someone came to you and said they aren't going to a party, and you knew someone at that party had specifically threatened to beat them if they attend the party, do you have "no reason" to believe that the threat of a beating is a likely cause of the action (or in these cases, inaction). Especially if that person has a long history of attending that specific party?