Nexstar adds former Verizon Chief Media Officer Tony Wells to its board, filling seat vacated when Dennis Miller left in October to become CW Network president ... Dun & Bradstreet adds former Google Cloud Americas President Kirsten Kliphouse to its board ... Yahoo Sports names Kendall Baker, ex-Axios Sports, senior writer ... Rivada Space Networks hires former Singtel, AsiaSat and SES executive Donald Chew as vice president-sales, Asia Pacific, based in Singapore ... Enterprise browser company Island names Forescout Technologies’ Steve Tchejeyan president ... Talkdesk adds former Salesforce.com Chief Financial Officer Graham Smith to its board ... Berkeley Research Group names Chris Stangl, ex-section chief in the FBI’s Cyber Division, managing director-cybersecurity and investigations practice in its D.C. office ... Pocket FM, audio streaming app for iOS and Android, promotes Vice President-Finance Anurag Sharma to CFO.