By Tzvi Machlin The Washington Commanders were plunged into a new scandal with former team employee Tiffani Johnston alleging that owner Dan Snyder placed his hand on her leg during a group dinner and later tried to cajole her into his limousine. In response, Snyder is getting an investigative team to look into the allegations. According to ESPN NFL insider Adam Schefter, Snyder is hiring “an independent investigative team, led by former Asst. U.S. Attorneys Bonnie Jonas and Tiffany Moller of Pallas Global Group LLC.” Leading the investigation will be Debra Wong Yang, a partner at Gibson, Dunn…